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examples.versioned_history.history_meta
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SQLAlchemy 0.9 Documentation
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Release: <span class="version-num">0.9.8</span> | Release Date: October 13, 2014
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<h1>SQLAlchemy 0.9 Documentation</h1>
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<h1>Source code for examples.versioned_history.history_meta</h1><div class="highlight"><pre>
<span class="sd">"""Versioned mixin class and other utilities."""</span>
<span class="kn">from</span> <span class="nn">sqlalchemy.ext.declarative</span> <span class="kn">import</span> <span class="n">declared_attr</span>
<span class="kn">from</span> <span class="nn">sqlalchemy.orm</span> <span class="kn">import</span> <span class="n">mapper</span><span class="p">,</span> <span class="n">attributes</span><span class="p">,</span> <span class="n">object_mapper</span>
<span class="kn">from</span> <span class="nn">sqlalchemy.orm.exc</span> <span class="kn">import</span> <span class="n">UnmappedColumnError</span>
<span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="n">Table</span><span class="p">,</span> <span class="n">Column</span><span class="p">,</span> <span class="n">ForeignKeyConstraint</span><span class="p">,</span> <span class="n">Integer</span><span class="p">,</span> <span class="n">DateTime</span>
<span class="kn">from</span> <span class="nn">sqlalchemy</span> <span class="kn">import</span> <span class="n">event</span>
<span class="kn">import</span> <span class="nn">datetime</span>
<span class="kn">from</span> <span class="nn">sqlalchemy.orm.properties</span> <span class="kn">import</span> <span class="n">RelationshipProperty</span>
<span class="k">def</span> <span class="nf">col_references_table</span><span class="p">(</span><span class="n">col</span><span class="p">,</span> <span class="n">table</span><span class="p">):</span>
<span class="k">for</span> <span class="n">fk</span> <span class="ow">in</span> <span class="n">col</span><span class="o">.</span><span class="n">foreign_keys</span><span class="p">:</span>
<span class="k">if</span> <span class="n">fk</span><span class="o">.</span><span class="n">references</span><span class="p">(</span><span class="n">table</span><span class="p">):</span>
<span class="k">return</span> <span class="bp">True</span>
<span class="k">return</span> <span class="bp">False</span>
<span class="k">def</span> <span class="nf">_is_versioning_col</span><span class="p">(</span><span class="n">col</span><span class="p">):</span>
<span class="k">return</span> <span class="s">"version_meta"</span> <span class="ow">in</span> <span class="n">col</span><span class="o">.</span><span class="n">info</span>
<span class="k">def</span> <span class="nf">_history_mapper</span><span class="p">(</span><span class="n">local_mapper</span><span class="p">):</span>
<span class="n">cls</span> <span class="o">=</span> <span class="n">local_mapper</span><span class="o">.</span><span class="n">class_</span>
<span class="c"># set the "active_history" flag</span>
<span class="c"># on on column-mapped attributes so that the old version</span>
<span class="c"># of the info is always loaded (currently sets it on all attributes)</span>
<span class="k">for</span> <span class="n">prop</span> <span class="ow">in</span> <span class="n">local_mapper</span><span class="o">.</span><span class="n">iterate_properties</span><span class="p">:</span>
<span class="nb">getattr</span><span class="p">(</span><span class="n">local_mapper</span><span class="o">.</span><span class="n">class_</span><span class="p">,</span> <span class="n">prop</span><span class="o">.</span><span class="n">key</span><span class="p">)</span><span class="o">.</span><span class="n">impl</span><span class="o">.</span><span class="n">active_history</span> <span class="o">=</span> <span class="bp">True</span>
<span class="n">super_mapper</span> <span class="o">=</span> <span class="n">local_mapper</span><span class="o">.</span><span class="n">inherits</span>
<span class="n">super_history_mapper</span> <span class="o">=</span> <span class="nb">getattr</span><span class="p">(</span><span class="n">cls</span><span class="p">,</span> <span class="s">'__history_mapper__'</span><span class="p">,</span> <span class="bp">None</span><span class="p">)</span>
<span class="n">polymorphic_on</span> <span class="o">=</span> <span class="bp">None</span>
<span class="n">super_fks</span> <span class="o">=</span> <span class="p">[]</span>
<span class="k">def</span> <span class="nf">_col_copy</span><span class="p">(</span><span class="n">col</span><span class="p">):</span>
<span class="n">col</span> <span class="o">=</span> <span class="n">col</span><span class="o">.</span><span class="n">copy</span><span class="p">()</span>
<span class="n">col</span><span class="o">.</span><span class="n">unique</span> <span class="o">=</span> <span class="bp">False</span>
<span class="n">col</span><span class="o">.</span><span class="n">default</span> <span class="o">=</span> <span class="n">col</span><span class="o">.</span><span class="n">server_default</span> <span class="o">=</span> <span class="bp">None</span>
<span class="k">return</span> <span class="n">col</span>
<span class="k">if</span> <span class="ow">not</span> <span class="n">super_mapper</span> <span class="ow">or</span> <span class="n">local_mapper</span><span class="o">.</span><span class="n">local_table</span> <span class="ow">is</span> <span class="ow">not</span> <span class="n">super_mapper</span><span class="o">.</span><span class="n">local_table</span><span class="p">:</span>
<span class="n">cols</span> <span class="o">=</span> <span class="p">[]</span>
<span class="k">for</span> <span class="n">column</span> <span class="ow">in</span> <span class="n">local_mapper</span><span class="o">.</span><span class="n">local_table</span><span class="o">.</span><span class="n">c</span><span class="p">:</span>
<span class="k">if</span> <span class="n">_is_versioning_col</span><span class="p">(</span><span class="n">column</span><span class="p">):</span>
<span class="k">continue</span>
<span class="n">col</span> <span class="o">=</span> <span class="n">_col_copy</span><span class="p">(</span><span class="n">column</span><span class="p">)</span>
<span class="k">if</span> <span class="n">super_mapper</span> <span class="ow">and</span> <span class="n">col_references_table</span><span class="p">(</span><span class="n">column</span><span class="p">,</span> <span class="n">super_mapper</span><span class="o">.</span><span class="n">local_table</span><span class="p">):</span>
<span class="n">super_fks</span><span class="o">.</span><span class="n">append</span><span class="p">((</span><span class="n">col</span><span class="o">.</span><span class="n">key</span><span class="p">,</span> <span class="nb">list</span><span class="p">(</span><span class="n">super_history_mapper</span><span class="o">.</span><span class="n">local_table</span><span class="o">.</span><span class="n">primary_key</span><span class="p">)[</span><span class="mi">0</span><span class="p">]))</span>
<span class="n">cols</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">col</span><span class="p">)</span>
<span class="k">if</span> <span class="n">column</span> <span class="ow">is</span> <span class="n">local_mapper</span><span class="o">.</span><span class="n">polymorphic_on</span><span class="p">:</span>
<span class="n">polymorphic_on</span> <span class="o">=</span> <span class="n">col</span>
<span class="k">if</span> <span class="n">super_mapper</span><span class="p">:</span>
<span class="n">super_fks</span><span class="o">.</span><span class="n">append</span><span class="p">((</span><span class="s">'version'</span><span class="p">,</span> <span class="n">super_history_mapper</span><span class="o">.</span><span class="n">local_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">version</span><span class="p">))</span>
<span class="n">version_meta</span> <span class="o">=</span> <span class="p">{</span><span class="s">"version_meta"</span><span class="p">:</span> <span class="bp">True</span><span class="p">}</span> <span class="c"># add column.info to identify</span>
<span class="c"># columns specific to versioning</span>
<span class="c"># "version" stores the integer version id. This column is</span>
<span class="c"># required.</span>
<span class="n">cols</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">Column</span><span class="p">(</span><span class="s">'version'</span><span class="p">,</span> <span class="n">Integer</span><span class="p">,</span> <span class="n">primary_key</span><span class="o">=</span><span class="bp">True</span><span class="p">,</span>
<span class="n">autoincrement</span><span class="o">=</span><span class="bp">False</span><span class="p">,</span> <span class="n">info</span><span class="o">=</span><span class="n">version_meta</span><span class="p">))</span>
<span class="c"># "changed" column stores the UTC timestamp of when the</span>
<span class="c"># history row was created.</span>
<span class="c"># This column is optional and can be omitted.</span>
<span class="n">cols</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">Column</span><span class="p">(</span><span class="s">'changed'</span><span class="p">,</span> <span class="n">DateTime</span><span class="p">,</span>
<span class="n">default</span><span class="o">=</span><span class="n">datetime</span><span class="o">.</span><span class="n">datetime</span><span class="o">.</span><span class="n">utcnow</span><span class="p">,</span>
<span class="n">info</span><span class="o">=</span><span class="n">version_meta</span><span class="p">))</span>
<span class="k">if</span> <span class="n">super_fks</span><span class="p">:</span>
<span class="n">cols</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">ForeignKeyConstraint</span><span class="p">(</span><span class="o">*</span><span class="nb">zip</span><span class="p">(</span><span class="o">*</span><span class="n">super_fks</span><span class="p">)))</span>
<span class="n">table</span> <span class="o">=</span> <span class="n">Table</span><span class="p">(</span><span class="n">local_mapper</span><span class="o">.</span><span class="n">local_table</span><span class="o">.</span><span class="n">name</span> <span class="o">+</span> <span class="s">'_history'</span><span class="p">,</span>
<span class="n">local_mapper</span><span class="o">.</span><span class="n">local_table</span><span class="o">.</span><span class="n">metadata</span><span class="p">,</span>
<span class="o">*</span><span class="n">cols</span><span class="p">,</span>
<span class="n">schema</span><span class="o">=</span><span class="n">local_mapper</span><span class="o">.</span><span class="n">local_table</span><span class="o">.</span><span class="n">schema</span>
<span class="p">)</span>
<span class="k">else</span><span class="p">:</span>
<span class="c"># single table inheritance. take any additional columns that may have</span>
<span class="c"># been added and add them to the history table.</span>
<span class="k">for</span> <span class="n">column</span> <span class="ow">in</span> <span class="n">local_mapper</span><span class="o">.</span><span class="n">local_table</span><span class="o">.</span><span class="n">c</span><span class="p">:</span>
<span class="k">if</span> <span class="n">column</span><span class="o">.</span><span class="n">key</span> <span class="ow">not</span> <span class="ow">in</span> <span class="n">super_history_mapper</span><span class="o">.</span><span class="n">local_table</span><span class="o">.</span><span class="n">c</span><span class="p">:</span>
<span class="n">col</span> <span class="o">=</span> <span class="n">_col_copy</span><span class="p">(</span><span class="n">column</span><span class="p">)</span>
<span class="n">super_history_mapper</span><span class="o">.</span><span class="n">local_table</span><span class="o">.</span><span class="n">append_column</span><span class="p">(</span><span class="n">col</span><span class="p">)</span>
<span class="n">table</span> <span class="o">=</span> <span class="bp">None</span>
<span class="k">if</span> <span class="n">super_history_mapper</span><span class="p">:</span>
<span class="n">bases</span> <span class="o">=</span> <span class="p">(</span><span class="n">super_history_mapper</span><span class="o">.</span><span class="n">class_</span><span class="p">,)</span>
<span class="k">else</span><span class="p">:</span>
<span class="n">bases</span> <span class="o">=</span> <span class="n">local_mapper</span><span class="o">.</span><span class="n">base_mapper</span><span class="o">.</span><span class="n">class_</span><span class="o">.</span><span class="n">__bases__</span>
<span class="n">versioned_cls</span> <span class="o">=</span> <span class="nb">type</span><span class="o">.</span><span class="n">__new__</span><span class="p">(</span><span class="nb">type</span><span class="p">,</span> <span class="s">"</span><span class="si">%s</span><span class="s">History"</span> <span class="o">%</span> <span class="n">cls</span><span class="o">.</span><span class="n">__name__</span><span class="p">,</span> <span class="n">bases</span><span class="p">,</span> <span class="p">{})</span>
<span class="n">m</span> <span class="o">=</span> <span class="n">mapper</span><span class="p">(</span>
<span class="n">versioned_cls</span><span class="p">,</span>
<span class="n">table</span><span class="p">,</span>
<span class="n">inherits</span><span class="o">=</span><span class="n">super_history_mapper</span><span class="p">,</span>
<span class="n">polymorphic_on</span><span class="o">=</span><span class="n">polymorphic_on</span><span class="p">,</span>
<span class="n">polymorphic_identity</span><span class="o">=</span><span class="n">local_mapper</span><span class="o">.</span><span class="n">polymorphic_identity</span>
<span class="p">)</span>
<span class="n">cls</span><span class="o">.</span><span class="n">__history_mapper__</span> <span class="o">=</span> <span class="n">m</span>
<span class="k">if</span> <span class="ow">not</span> <span class="n">super_history_mapper</span><span class="p">:</span>
<span class="n">local_mapper</span><span class="o">.</span><span class="n">local_table</span><span class="o">.</span><span class="n">append_column</span><span class="p">(</span>
<span class="n">Column</span><span class="p">(</span><span class="s">'version'</span><span class="p">,</span> <span class="n">Integer</span><span class="p">,</span> <span class="n">default</span><span class="o">=</span><span class="mi">1</span><span class="p">,</span> <span class="n">nullable</span><span class="o">=</span><span class="bp">False</span><span class="p">)</span>
<span class="p">)</span>
<span class="n">local_mapper</span><span class="o">.</span><span class="n">add_property</span><span class="p">(</span><span class="s">"version"</span><span class="p">,</span> <span class="n">local_mapper</span><span class="o">.</span><span class="n">local_table</span><span class="o">.</span><span class="n">c</span><span class="o">.</span><span class="n">version</span><span class="p">)</span>
<span class="k">class</span> <span class="nc">Versioned</span><span class="p">(</span><span class="nb">object</span><span class="p">):</span>
<span class="nd">@declared_attr</span>
<span class="k">def</span> <span class="nf">__mapper_cls__</span><span class="p">(</span><span class="n">cls</span><span class="p">):</span>
<span class="k">def</span> <span class="nf">map</span><span class="p">(</span><span class="n">cls</span><span class="p">,</span> <span class="o">*</span><span class="n">arg</span><span class="p">,</span> <span class="o">**</span><span class="n">kw</span><span class="p">):</span>
<span class="n">mp</span> <span class="o">=</span> <span class="n">mapper</span><span class="p">(</span><span class="n">cls</span><span class="p">,</span> <span class="o">*</span><span class="n">arg</span><span class="p">,</span> <span class="o">**</span><span class="n">kw</span><span class="p">)</span>
<span class="n">_history_mapper</span><span class="p">(</span><span class="n">mp</span><span class="p">)</span>
<span class="k">return</span> <span class="n">mp</span>
<span class="k">return</span> <span class="nb">map</span>
<span class="k">def</span> <span class="nf">versioned_objects</span><span class="p">(</span><span class="nb">iter</span><span class="p">):</span>
<span class="k">for</span> <span class="n">obj</span> <span class="ow">in</span> <span class="nb">iter</span><span class="p">:</span>
<span class="k">if</span> <span class="nb">hasattr</span><span class="p">(</span><span class="n">obj</span><span class="p">,</span> <span class="s">'__history_mapper__'</span><span class="p">):</span>
<span class="k">yield</span> <span class="n">obj</span>
<span class="k">def</span> <span class="nf">create_version</span><span class="p">(</span><span class="n">obj</span><span class="p">,</span> <span class="n">session</span><span class="p">,</span> <span class="n">deleted</span><span class="o">=</span><span class="bp">False</span><span class="p">):</span>
<span class="n">obj_mapper</span> <span class="o">=</span> <span class="n">object_mapper</span><span class="p">(</span><span class="n">obj</span><span class="p">)</span>
<span class="n">history_mapper</span> <span class="o">=</span> <span class="n">obj</span><span class="o">.</span><span class="n">__history_mapper__</span>
<span class="n">history_cls</span> <span class="o">=</span> <span class="n">history_mapper</span><span class="o">.</span><span class="n">class_</span>
<span class="n">obj_state</span> <span class="o">=</span> <span class="n">attributes</span><span class="o">.</span><span class="n">instance_state</span><span class="p">(</span><span class="n">obj</span><span class="p">)</span>
<span class="n">attr</span> <span class="o">=</span> <span class="p">{}</span>
<span class="n">obj_changed</span> <span class="o">=</span> <span class="bp">False</span>
<span class="k">for</span> <span class="n">om</span><span class="p">,</span> <span class="n">hm</span> <span class="ow">in</span> <span class="nb">zip</span><span class="p">(</span><span class="n">obj_mapper</span><span class="o">.</span><span class="n">iterate_to_root</span><span class="p">(),</span> <span class="n">history_mapper</span><span class="o">.</span><span class="n">iterate_to_root</span><span class="p">()):</span>
<span class="k">if</span> <span class="n">hm</span><span class="o">.</span><span class="n">single</span><span class="p">:</span>
<span class="k">continue</span>
<span class="k">for</span> <span class="n">hist_col</span> <span class="ow">in</span> <span class="n">hm</span><span class="o">.</span><span class="n">local_table</span><span class="o">.</span><span class="n">c</span><span class="p">:</span>
<span class="k">if</span> <span class="n">_is_versioning_col</span><span class="p">(</span><span class="n">hist_col</span><span class="p">):</span>
<span class="k">continue</span>
<span class="n">obj_col</span> <span class="o">=</span> <span class="n">om</span><span class="o">.</span><span class="n">local_table</span><span class="o">.</span><span class="n">c</span><span class="p">[</span><span class="n">hist_col</span><span class="o">.</span><span class="n">key</span><span class="p">]</span>
<span class="c"># get the value of the</span>
<span class="c"># attribute based on the MapperProperty related to the</span>
<span class="c"># mapped column. this will allow usage of MapperProperties</span>
<span class="c"># that have a different keyname than that of the mapped column.</span>
<span class="k">try</span><span class="p">:</span>
<span class="n">prop</span> <span class="o">=</span> <span class="n">obj_mapper</span><span class="o">.</span><span class="n">get_property_by_column</span><span class="p">(</span><span class="n">obj_col</span><span class="p">)</span>
<span class="k">except</span> <span class="n">UnmappedColumnError</span><span class="p">:</span>
<span class="c"># in the case of single table inheritance, there may be</span>
<span class="c"># columns on the mapped table intended for the subclass only.</span>
<span class="c"># the "unmapped" status of the subclass column on the</span>
<span class="c"># base class is a feature of the declarative module as of sqla 0.5.2.</span>
<span class="k">continue</span>
<span class="c"># expired object attributes and also deferred cols might not be in the</span>
<span class="c"># dict. force it to load no matter what by using getattr().</span>
<span class="k">if</span> <span class="n">prop</span><span class="o">.</span><span class="n">key</span> <span class="ow">not</span> <span class="ow">in</span> <span class="n">obj_state</span><span class="o">.</span><span class="n">dict</span><span class="p">:</span>
<span class="nb">getattr</span><span class="p">(</span><span class="n">obj</span><span class="p">,</span> <span class="n">prop</span><span class="o">.</span><span class="n">key</span><span class="p">)</span>
<span class="n">a</span><span class="p">,</span> <span class="n">u</span><span class="p">,</span> <span class="n">d</span> <span class="o">=</span> <span class="n">attributes</span><span class="o">.</span><span class="n">get_history</span><span class="p">(</span><span class="n">obj</span><span class="p">,</span> <span class="n">prop</span><span class="o">.</span><span class="n">key</span><span class="p">)</span>
<span class="k">if</span> <span class="n">d</span><span class="p">:</span>
<span class="n">attr</span><span class="p">[</span><span class="n">hist_col</span><span class="o">.</span><span class="n">key</span><span class="p">]</span> <span class="o">=</span> <span class="n">d</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span>
<span class="n">obj_changed</span> <span class="o">=</span> <span class="bp">True</span>
<span class="k">elif</span> <span class="n">u</span><span class="p">:</span>
<span class="n">attr</span><span class="p">[</span><span class="n">hist_col</span><span class="o">.</span><span class="n">key</span><span class="p">]</span> <span class="o">=</span> <span class="n">u</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span>
<span class="k">else</span><span class="p">:</span>
<span class="c"># if the attribute had no value.</span>
<span class="n">attr</span><span class="p">[</span><span class="n">hist_col</span><span class="o">.</span><span class="n">key</span><span class="p">]</span> <span class="o">=</span> <span class="n">a</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span>
<span class="n">obj_changed</span> <span class="o">=</span> <span class="bp">True</span>
<span class="k">if</span> <span class="ow">not</span> <span class="n">obj_changed</span><span class="p">:</span>
<span class="c"># not changed, but we have relationships. OK</span>
<span class="c"># check those too</span>
<span class="k">for</span> <span class="n">prop</span> <span class="ow">in</span> <span class="n">obj_mapper</span><span class="o">.</span><span class="n">iterate_properties</span><span class="p">:</span>
<span class="k">if</span> <span class="nb">isinstance</span><span class="p">(</span><span class="n">prop</span><span class="p">,</span> <span class="n">RelationshipProperty</span><span class="p">)</span> <span class="ow">and</span> \
<span class="n">attributes</span><span class="o">.</span><span class="n">get_history</span><span class="p">(</span><span class="n">obj</span><span class="p">,</span> <span class="n">prop</span><span class="o">.</span><span class="n">key</span><span class="p">,</span>
<span class="n">passive</span><span class="o">=</span><span class="n">attributes</span><span class="o">.</span><span class="n">PASSIVE_NO_INITIALIZE</span><span class="p">)</span><span class="o">.</span><span class="n">has_changes</span><span class="p">():</span>
<span class="k">for</span> <span class="n">p</span> <span class="ow">in</span> <span class="n">prop</span><span class="o">.</span><span class="n">local_columns</span><span class="p">:</span>
<span class="k">if</span> <span class="n">p</span><span class="o">.</span><span class="n">foreign_keys</span><span class="p">:</span>
<span class="n">obj_changed</span> <span class="o">=</span> <span class="bp">True</span>
<span class="k">break</span>
<span class="k">if</span> <span class="n">obj_changed</span> <span class="ow">is</span> <span class="bp">True</span><span class="p">:</span>
<span class="k">break</span>
<span class="k">if</span> <span class="ow">not</span> <span class="n">obj_changed</span> <span class="ow">and</span> <span class="ow">not</span> <span class="n">deleted</span><span class="p">:</span>
<span class="k">return</span>
<span class="n">attr</span><span class="p">[</span><span class="s">'version'</span><span class="p">]</span> <span class="o">=</span> <span class="n">obj</span><span class="o">.</span><span class="n">version</span>
<span class="n">hist</span> <span class="o">=</span> <span class="n">history_cls</span><span class="p">()</span>
<span class="k">for</span> <span class="n">key</span><span class="p">,</span> <span class="n">value</span> <span class="ow">in</span> <span class="n">attr</span><span class="o">.</span><span class="n">items</span><span class="p">():</span>
<span class="nb">setattr</span><span class="p">(</span><span class="n">hist</span><span class="p">,</span> <span class="n">key</span><span class="p">,</span> <span class="n">value</span><span class="p">)</span>
<span class="n">session</span><span class="o">.</span><span class="n">add</span><span class="p">(</span><span class="n">hist</span><span class="p">)</span>
<span class="n">obj</span><span class="o">.</span><span class="n">version</span> <span class="o">+=</span> <span class="mi">1</span>
<span class="k">def</span> <span class="nf">versioned_session</span><span class="p">(</span><span class="n">session</span><span class="p">):</span>
<span class="nd">@event.listens_for</span><span class="p">(</span><span class="n">session</span><span class="p">,</span> <span class="s">'before_flush'</span><span class="p">)</span>
<span class="k">def</span> <span class="nf">before_flush</span><span class="p">(</span><span class="n">session</span><span class="p">,</span> <span class="n">flush_context</span><span class="p">,</span> <span class="n">instances</span><span class="p">):</span>
<span class="k">for</span> <span class="n">obj</span> <span class="ow">in</span> <span class="n">versioned_objects</span><span class="p">(</span><span class="n">session</span><span class="o">.</span><span class="n">dirty</span><span class="p">):</span>
<span class="n">create_version</span><span class="p">(</span><span class="n">obj</span><span class="p">,</span> <span class="n">session</span><span class="p">)</span>
<span class="k">for</span> <span class="n">obj</span> <span class="ow">in</span> <span class="n">versioned_objects</span><span class="p">(</span><span class="n">session</span><span class="o">.</span><span class="n">deleted</span><span class="p">):</span>
<span class="n">create_version</span><span class="p">(</span><span class="n">obj</span><span class="p">,</span> <span class="n">session</span><span class="p">,</span> <span class="n">deleted</span><span class="o">=</span><span class="bp">True</span><span class="p">)</span></pre></div>
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