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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 check_xlim_change(self):
        '''check for new X bounds'''
        if self.xlim_pipe is None:
            return None
        xlim = None
        while self.xlim_pipe[0].poll():
            try:
                xlim = self.xlim_pipe[0].recv()
            except EOFError:
                return None
        if xlim != self.xlim:
            return xlim
        return None