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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 process(self, body, url=None, sig=None):
 """Process request body given skill logic. To validate a request, both, url and sig are required. Attributes received through body will be automatically added to the response. Args: body: str. HTTP request body. url: str. SignatureCertChainUrl header value sent by request. PEM-encoded X.509 certificate chain that Alexa used to sign the message. sig: str. Signature header value sent by request. Base64-encoded signature of the request body. Return: str or bool: HTTP response body or False if the request is invalid. """

        self.request = RequestBody()
        self.response = ResponseBody()

        self.request.parse(body)

        app_id = self.request.session.application.application_id
        stamp = self.request.request.timestamp
        if not self.valid.request(app_id, body, stamp, url, sig):
            return False

        self.pass_session_attributes()

        self.dispatch()

        if self.request.request.type == 'SessionEndedRequest':
            self.terminate()

        return self.response.to_json()