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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 __set_web_authentication_detail(self):
 """ Sets up the WebAuthenticationDetail node. This is required for all requests. """


        # Start of the authentication stuff.
        web_authentication_credential = self.client.factory.create('WebAuthenticationCredential')
        web_authentication_credential.Key = self.config_obj.key
        web_authentication_credential.Password = self.config_obj.password

        # Encapsulates the auth credentials.
        web_authentication_detail = self.client.factory.create('WebAuthenticationDetail')
        web_authentication_detail.UserCredential = web_authentication_credential

        # Set Default ParentCredential
        if hasattr(web_authentication_detail, 'ParentCredential'):
            web_authentication_detail.ParentCredential = web_authentication_credential

        self.WebAuthenticationDetail = web_authentication_detail