def package_by_id(self, package_id):
        """Retrieve a package from its id.

        Arguments
        ---------
        package_id: str
            A package id
        """
        try:
            return self._packages_by_id[package_id]
        except __HOLE__:
            raise MissingPackageInfoInPool(package_id)
dataset/ETHPy150Open enthought/depsolver/depsolver/pool.py/Pool.package_by_id