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