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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 _get_whl_from_dir(cls, install_dir):
 """Return the absolute path of the whl in a setup.py install directory."""

    dist_dir = cls._get_dist_dir(install_dir)
    dists = glob.glob(os.path.join(dist_dir, '*.whl'))
    if len(dists) == 0:
      raise cls.BuildLocalPythonDistributionsError(
        'No distributions were produced by python_create_distribution task.\n'
        'dist_dir: {}, install_dir: {}'
        .format(dist_dir, install_dir))
    if len(dists) > 1:
      # TODO: is this ever going to happen?
      raise cls.BuildLocalPythonDistributionsError('Ambiguous local python distributions found: {}'
                                                   .format(dists))
    return dists[0]