docs: 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