def map_version(self, requirement, local_version):
        """
        Maps a local version name to one recognised by the Requirement class

        Parameters
        ----------
        requirement : str
            Name of the requirement
        version : str
            version string
        """
        if isinstance(self._versions_map, dict):
            version = self._versions_map.get(requirement, {}).get(
                local_version, local_version)
        else:
            version = self._versions_map(requirement, local_version)
        return version