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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_basis_family(basis_name, data_dir=None):
    '''Lookup a family by a basis set name
    '''

    data_dir = fix_data_dir(data_dir)
    bs_data = _get_basis_metadata(basis_name, data_dir)
    return bs_data['family']