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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 user(self, username=None):
 """gets the user's content. If None is passed, the current user is used. Input: username - name of the login for a given user on a site. """

        if username is None:
            username = self.__getUsername()

        url = "%s/%s" % (self.root, username)
        return User(url=url,
                    securityHandler=self._securityHandler,
                    proxy_url=self._proxy_url,
                    proxy_port=self._proxy_port,
                    initalize=True)