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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 ciphertext_length(header, plaintext_length):
 """Calculates the complete ciphertext message length, given a complete header. :param header: Complete message header object :type header: aws_encryption_sdk.structures.MessageHeader :param int plaintext_length: Length of plaintext in bytes :rtype: int """

    ciphertext_length = header_length(header)
    ciphertext_length += body_length(header, plaintext_length)
    ciphertext_length += footer_length(header)
    return ciphertext_length