Replace pkg_resources with importlib.metadata

src/batou/lib/python.py

@@ -62,7 +62,6 @@ def verify(self):
         )
         # Is this Python (still) functional 'enough'
         # from a setuptools/distribute perspective?
-        self.assert_cmd('bin/python -c "import pkg_resources"')
         self.assert_cmd('bin/python -c "import pip"')
 
     def update(self):
@@ -71,30 +70,13 @@ def update(self):
 
     def verify_pkg(self, pkg):
         try:
-            self.cmd(
-                'bin/python -c "'
-                "import pkg_resources; "
-                "assert pkg_resources.require('{}')[0].parsed_version == "
-                "pkg_resources.parse_version('{}')\"".format(
-                    pkg.package, pkg.version
-                )
-            )
+            self.cmd('bin/python -c \''
+                     'import importlib.metadata; '
+                     f'assert importlib.metadata.version("{pkg.package}") == '
+                     f' "{pkg.version}"'
+                     '\'')
         except CmdExecutionError:
             raise batou.UpdateNeeded()
-        # Is the package usable? Is the package a module?  This might be
-        # overspecific - I'm looking for a way to deal with:
-        # https://github.com/pypa/pip/issues/3 if a namespace package was not
-        # installed cleanly. This only works (currently), when the package name
-        # corresponds with what it contains. I.E. it works for zc.buildout but
-        # not for distribute, which installs a setuptools package.
-        if pkg.check_package_is_module:
-            try:
-                self.cmd(
-                    'bin/python -c "import pkg_resources; '
-                    'import {0};{0}.__file__"'.format(pkg.package)
-                )
-            except CmdExecutionError:
-                raise batou.UpdateNeeded()
 
     def update_pkg(self, pkg):
         if self.installer == "pip":