code: def get(self, artifact):
      
      coord = self._key(artifact)
      if coord in self._artifacts_to_versions:
        return self._artifacts_to_versions[coord]
      return artifact
docs: Gets the coordinate with the correct version for the given artifact coordinate.
  
      :param M2Coordinate artifact: the coordinate to lookup.
      :return: a coordinate which is the same as the input, but with the correct pinned version. If
        this artifact set does not pin a version for the input artifact, this just returns the
        original coordinate.
      :rtype: M2Coordinate