Author: Luca Boccassi <bluca@debian.org>
Description: look for extensions in /usr/lib/python3/dist-packages instead of /usr/local/lib/python3.x/dist-packages
--- a/src/azure-cli-core/azure/cli/core/extension/__init__.py
+++ b/src/azure-cli-core/azure/cli/core/extension/__init__.py
@@ -22,7 +22,7 @@
 EXTENSIONS_DIR = os.path.expanduser(_CUSTOM_EXT_DIR) if _CUSTOM_EXT_DIR else os.path.join(GLOBAL_CONFIG_DIR,
                                                                                           'cliextensions')
 DEV_EXTENSION_SOURCES = _DEV_EXTENSION_SOURCES.split(',') if _DEV_EXTENSION_SOURCES else []
-EXTENSIONS_SYS_DIR = os.path.expanduser(_CUSTOM_EXT_SYS_DIR) if _CUSTOM_EXT_SYS_DIR else os.path.join(get_path("purelib"), 'azure-cli-extensions')
+EXTENSIONS_SYS_DIR = os.path.expanduser(_CUSTOM_EXT_SYS_DIR) if _CUSTOM_EXT_SYS_DIR else os.path.join(get_path("purelib", "deb_system"), 'azure-cli-extensions')
 
 EXTENSIONS_MOD_PREFIX = 'azext_'