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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 _get_char(self):
 """Read a character from input. @rtype: string """


        if self.ungotten_char is None:
            if self.eof:
                c = ''
            else:
                c = self.file.read(1)
                if c == '':
                    self.eof = True
                elif c == '\n':
                    self.line_number += 1
        else:
            c = self.ungotten_char
            self.ungotten_char = None
        return c