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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 add_to_stage(self, paths):
 """Stage given files :param paths: :return: """

        cmd = self._command.add(paths)

        (code, stdout, stderr) = self._exec(cmd)

        if code:
            raise errors.VCSError('Can\'t add paths to VCS. Process exited with code %d and message: %s' % (
                code, stderr + stdout))