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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 basic_decrypt() -> Response: """Basic decrypt handler for decrypt oracle v0. **Request** * **Method**: POST * **Body**: Raw ciphertext bytes * **Headers**: * **Content-Type**: ``application/octet-stream`` * **Accept**: ``application/octet-stream`` **Response** * 200 response code with the raw plaintext bytes as the body * 400 response code with whatever error code was encountered as the body """

    APP.log.debug("Request:")
    APP.log.debug(json.dumps(APP.current_request.to_dict()))
    APP.log.debug("Ciphertext:")
    APP.log.debug(APP.current_request.raw_body)

    try:
        ciphertext = APP.current_request.raw_body
        plaintext, _header = aws_encryption_sdk.decrypt(source=ciphertext, key_provider=_master_key_provider())
        APP.log.debug("Plaintext:")
        APP.log.debug(plaintext)
        response = Response(body=plaintext, headers={"Content-Type": "application/octet-stream"}, status_code=200)
    except Exception as error:  # pylint: disable=broad-except
        response = Response(body=str(error), status_code=400)

    APP.log.debug("Response:")
    APP.log.debug(json.dumps(response.to_dict(binary_types=["application/octet-stream"])))
    return response