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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 decrypt(algorithm, key, encrypted_data, associated_data):
 """Decrypts a frame body. :param algorithm: Algorithm used to encrypt this body :type algorithm: aws_encryption_sdk.identifiers.Algorithm :param bytes key: Plaintext data key :param encrypted_data: EncryptedData containing body data :type encrypted_data: :class:`aws_encryption_sdk.internal.structures.EncryptedData`, :class:`aws_encryption_sdk.internal.structures.FrameBody`, or :class:`aws_encryption_sdk.internal.structures.MessageNoFrameBody` :param bytes associated_data: AAD string generated for body :type associated_data: bytes :returns: Plaintext of body :rtype: bytes """

    decryptor = Decryptor(algorithm, key, associated_data, encrypted_data.iv, encrypted_data.tag)
    return decryptor.update(encrypted_data.ciphertext) + decryptor.finalize()