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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 removeFriend(self, user):
 """ Remove the specified user from all sharing. Parameters: user (str):
 MyPlexUser, username, email of the user to be added. """

        user = self.user(user)
        url = self.FRIENDUPDATE if user.friend else self.REMOVEINVITE
        url = url.format(userId=user.id)
        return self.query(url, self._session.delete)