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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 _debug(self, out, print_prefix=True):
 """ Print out to stderr, if debugging is enabled. """

        if self.debug:
            if print_prefix:
                pre = self.__class__.__name__
                if hasattr(self, 'debug_prefix'):
                    pre = getattr(self, 'debug_prefix')
                sys.stderr.write("%s: " % pre)
            sys.stderr.write(out)