<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def package_releases(self, project_name):
 """ Retrieve the versions from PyPI by ``project_name``. Args: project_name (str):
 The name of the project we wish to retrieve the versions of. Returns: list: Of string versions. """

        try:
            return self._connection.package_releases(project_name)
        except Exception as err:
            raise PyPIClientError(err)