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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 include(self, filename):
 """ Changes FILENAME and line count """

        if filename != STDIN and filename in [x[0] for x in self.filestack]:  # Already included?
            self.warning(' Recursive inclusion')

        self.filestack.append([filename, 1, self.lex, self.input_data])
        self.lex = lex.lex(object=self)
        result = self.put_current_line()  # First #line start with \n (EOL)

        try:
            if filename == STDIN:
                self.input_data = sys.stdin.read()
            else:
                self.input_data = api.utils.read_txt_file(filename)

            if len(self.input_data) and self.input_data[-1] != EOL:
                self.input_data += EOL
        except IOError:
            self.input_data = EOL

        self.lex.input(self.input_data)
        return result