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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 _final_frame_length(header, final_frame_bytes):
 """Calculates the length of a final ciphertext frame, given a complete header and the number of bytes of ciphertext in the final frame. :param header: Complete message header object :type header: aws_encryption_sdk.structures.MessageHeader :param int final_frame_bytes: Bytes of ciphertext in the final frame :rtype: int """

    final_frame_length = 4  # Sequence Number End
    final_frame_length += 4  # Sequence Number
    final_frame_length += header.algorithm.iv_len  # IV
    final_frame_length += 4  # Encrypted Content Length
    final_frame_length += final_frame_bytes  # Encrypted Content
    final_frame_length += header.algorithm.auth_len  # Authentication Tag
    return final_frame_length