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---
orphan:
---
# Example error: ResolutionImpossible
## What if there are user-provided pinned packages?
Where a user wants to install packages (with 1 or more pinned version)
with default verbose level
```
$ pip install peach=1.0 apple=2.0
Due to conflicting dependencies pip cannot install Peach1.0 and Apple2.0:
* Peach 1.0 depends on Banana 3.0
* Apple2.0 depends on Banana2.0
There are a number of possible solutions. You can try:
1. removing package versions from your requirements, and letting pip try to resolve the problem for you
2. Trying a version of Peach that depends on Banana2.0. Try `pip-search peach —dep banana2.0`
3. replacing Apple or Peach with a different package altogether
4. patching Apple2.0 to use Banana3.0
5. force installing (Be aware!)
For instructions on how to do these steps visit: https://pypa.io/SomeLink
To debug this further you can run `pip-tree` to see all of your dependencies.
```
**with verbose level -vv**
If a user ran the same pip command with more verbosity, what would they see?
**with verbose level -vvv**
If a user ran the same pip command with more verbosity, what would they see?
## What if there are no user-provided version restrictions?
NB: We are assuming this resolver behaviour gets implemented, based on [GH issues 8249](https://github.com/pypa/pip/issues/8249).
**with default verbose level**
```
$ pip install apple peach
Due to conflicting dependencies pip cannot install apple or peach. Both depend on banana, but pip can't find a version of either where they depend on the same banana version.
There are a number of possible solutions. You can try:
1. replacing apple or peach with a different package altogether
2. patching apple or peach to use the same version of banana
3. force installing (Be aware!)
To debug this further you can run pip-tree to see all of your dependencies.
```
**with verbose level -vv**
If a user ran the same pip command with more verbosity, what would they see?
**with verbose level -vvv**
If a user ran the same pip command with more verbosity, what would they see?
**What should be in the "documentation" page?**
* ways to swap a package for another
* how to patch a package to support a version (various ways)
## Recommendations
* Write official documentation / guide "How to resolve dependency conflicts" explaining:
* Why conflicts can exist
* How you can avoid them (pinning)
* How you can resolve them
* Use alternative package
* Use older version
* Patch package
* Introduce new commands to pip, inspired by poetry:
* Tree: Show full tree of dependencies
* Show `<package>` Show details of a package, including it's dependencies
* latest - shows latest vs installed versions
* outdated - shows only outdated versions
* Expose commands / help link in output??
* when particular issue happens provide ways to move on (ala pipenv), e.g.
* run this command to see X
* is it your internet connection?
* is it the pypi website?
* Aspirational commands
* `pip search PackageName —dep PackageNameVersion`
* a command that will search for a version of a package that has a dependency on another packageversion
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