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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 _compute_fingerprint(key):
 """ Given a RSA key, computes its fingerprint like Telegram does. :param key: the Crypto.RSA key. :return: its 8-bytes-long fingerprint. """

    n = TLObject.serialize_bytes(get_byte_array(key.n))
    e = TLObject.serialize_bytes(get_byte_array(key.e))
    # Telegram uses the last 8 bytes as the fingerprint
    return struct.unpack('<q', sha1(n + e).digest()[-8:])[0]