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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 sign_plaintext(client_secret, resource_owner_secret):
 """Sign a request using plaintext. Per `section 3.4.4`_ of the spec. The "PLAINTEXT" method does not employ a signature algorithm. It MUST be used with a transport-layer mechanism such as TLS or SSL (or sent over a secure channel with equivalent protections). It does not utilize the signature base string or the "oauth_timestamp" and "oauth_nonce" parameters. .. _`section 3.4.4`: https://tools.ietf.org/html/rfc5849#section-3.4.4 """


    # The "oauth_signature" protocol parameter is set to the concatenated
    # value of:

    # 1.  The client shared-secret, after being encoded (`Section 3.6`_).
    #
    # .. _`Section 3.6`: https://tools.ietf.org/html/rfc5849#section-3.6
    signature = utils.escape(client_secret or '')

    # 2.  An "&" character (ASCII code 38), which MUST be included even
    #     when either secret is empty.
    signature += '&'

    # 3.  The token shared-secret, after being encoded (`Section 3.6`_).
    #
    # .. _`Section 3.6`: https://tools.ietf.org/html/rfc5849#section-3.6
    signature += utils.escape(resource_owner_secret or '')

    return signature