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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 _closest_ref_length(references, trans_length):
 """Find the reference that has the closest length to the translation. Parameters references: list(list(str)) A list of references. trans_length: int Length of the translation. Returns ------- closest_ref_len: int Length of the reference that is closest to the translation. """

    ref_lengths = (len(reference) for reference in references)
    closest_ref_len = min(ref_lengths,
                          key=lambda ref_length: (abs(ref_length - trans_length), ref_length))

    return closest_ref_len