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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 _restriction_string(self):
 """Get a string explaining the expectation currently set e.g `at least 5 times`, `at most 1 time`, or `2 times` :rtype string """


        if self.has_minimum:
            string = 'at least '
            value = self._minimum
        elif self.has_maximum:
            string = 'at most '
            value = self._maximum
        elif self.has_exact:
            string = ''
            value = self._exact

        return (string + '{} {}').format(
            value,
            pluralize('time', value)
        )