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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 _standard_frame_length(header):
 """Calculates the length of a standard ciphertext frame, given a complete header. :param header: Complete message header object :type header: aws_encryption_sdk.structures.MessageHeader :rtype: int """

    frame_length = 4  # Sequence Number
    frame_length += header.algorithm.iv_len  # IV
    frame_length += header.frame_length  # Encrypted Content
    frame_length += header.algorithm.auth_len  # Authentication Tag
    return frame_length