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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 fail(self, msg, lineno=None, exc=TemplateSyntaxError):
 """Convenience method that raises `exc` with the message, passed line number or last line number as well as the current name and filename. """

        if lineno is None:
            lineno = self.stream.current.lineno
        raise exc(msg, lineno, self.name, self.filename)