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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 rt_update(self, statement, linenum, mode, xparser):
 """Uses the specified line parser to parse the given line. :arg statement: a string of lines that are part of a single statement. :arg linenum: the line number of the first line in the list relative to the entire module contents. arg mode: either 'insert', 'replace' or 'delete' :arg xparser: an instance of the executable parser from the real time update module's line parser. """

        section = self.find_section(self.module.charindex(linenum, 1))

        if section == "body":
            xparser.parse_line(statement, self, mode)
        elif section == "signature":
            if mode == "insert":
                xparser.parse_signature(statement, self)