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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 verify_plaintext(request, client_secret=None, resource_owner_secret=None):
 """Verify a PLAINTEXT signature. Per `section 3.4`_ of the spec. .. _`section 3.4`: https://tools.ietf.org/html/rfc5849#section-3.4 """

    signature = sign_plaintext(client_secret, resource_owner_secret)
    match = safe_string_equals(signature, request.signature)
    if not match:
        log.debug('Verify PLAINTEXT failed')
    return match