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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 update(self):
 """Update the user's details on Todoist. This method must be called to register any local attribute changes with Todoist. """

        args = {attr: getattr(self, attr) for attr in self.to_update}
        _perform_command(self, 'user_update', args)