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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 consume(self, char):
 """ Consume a single character and advance the state as necessary. """


        if self.state == "stream":
            self._stream(char)
        elif self.state == "escape":
            self._escape_sequence(char)
        elif self.state == "escape-lb":
            self._escape_parameters(char)
        elif self.state == "mode":
            self._mode(char)
        elif self.state == "charset-g0":
            self._charset_g0(char)
        elif self.state == "charset-g1":
            self._charset_g1(char)