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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def notes_for_version(self, version):
 """Given the parsed Version of pants, return its release notes. TODO: This method should parse out the specific version from the resulting file: see https://github.com/pantsbuild/pants/issues/1708 """

    branch_name = self._branch_name(version)
    branch_notes_file = self._branch_notes.get(branch_name, None)
    if branch_notes_file is None:
      raise ValueError(
          'Version {} lives in branch {}, which is not configured in {}.'.format(
            version, branch_name, self._branch_notes))
    return _read_contents(branch_notes_file)