Return a pkg_resources.Distribution for this requirement

def get_dist(self):
        # type: () -> Distribution
        """Return a pkg_resources.Distribution for this requirement"""
        if self.metadata_directory:
            base_dir, distinfo = os.path.split(self.metadata_directory)
            metadata = pkg_resources.PathMetadata(
                base_dir, self.metadata_directory
            )
            dist_name = os.path.splitext(distinfo)[0]
            typ = pkg_resources.DistInfoDistribution
        else:
            egg_info = self.egg_info_path.rstrip(os.path.sep)
            base_dir = os.path.dirname(egg_info)
            metadata = pkg_resources.PathMetadata(base_dir, egg_info)
            dist_name = os.path.splitext(os.path.basename(egg_info))[0]
            # https://github.com/python/mypy/issues/1174
            typ = pkg_resources.Distribution  # type: ignore

        return typ(
            base_dir,
            project_name=dist_name,
            metadata=metadata,
        )