ah_bootstrap.py 文件源码

def get_local_directory_dist(self):
        """
        Handle importing a vendored package from a subdirectory of the source
        distribution.
        """

        if not os.path.isdir(self.path):
            return

        log.info('Attempting to import astropy_helpers from {0} {1!r}'.format(
                 'submodule' if self.is_submodule else 'directory',
                 self.path))

        dist = self._directory_import()

        if dist is None:
            log.warn(
                'The requested path {0!r} for importing {1} does not '
                'exist, or does not contain a copy of the {1} '
                'package.'.format(self.path, PACKAGE_NAME))
        elif self.auto_upgrade and not self.is_submodule:
            # A version of astropy-helpers was found on the available path, but
            # check to see if a bugfix release is available on PyPI
            upgrade = self._do_upgrade(dist)
            if upgrade is not None:
                dist = upgrade

        return dist