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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 save(self, branch, commit_message, **kwargs):
 """Save the changes made to the file to the server. The object is updated to match what the server returns. Args: branch (str):
 Branch in which the file will be updated commit_message (str):
 Message to send with the commit **kwargs: Extra options to send to the server (e.g. sudo) Raises: GitlabAuthenticationError: If authentication is not correct GitlabUpdateError: If the server cannot perform the request """

        self.branch = branch
        self.commit_message = commit_message
        self.file_path = self.file_path.replace('/', '%2F')
        super(ProjectFile, self).save(**kwargs)