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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 ReplaceUser(self, user_link, user, options=None):
 """Replaces a user and return it. :param str user_link: The link to the user entity. :param dict user: :param dict options: The request options for the request. :return: The new User. :rtype: dict """

        if options is None:
            options = {}

        CosmosClient.__ValidateResource(user)
        path = base.GetPathFromLink(user_link)
        user_id = base.GetResourceIdOrFullNameFromLink(user_link)
        return self.Replace(user,
                            path,
                            'users',
                            user_id,
                            None,
                            options)