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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 _process_version_lines(self):
 """Process version line rules."""

        if len(self._lines_seen["version"]) > 1:
            self._add_error(_("Multiple version lines appeared."))
        elif self._lines_seen["version"][0] != 1:
            self._add_error(_("The version must be on the first line."))