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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 error_string(self):
 """Returns a well formed error message e.g at least 5 times but was called 4 times :rtype string """


        if self.has_correct_call_count():
            return ''

        return '{} instead of {} {} '.format(
            self._restriction_string(),
            self.count,
            pluralize('time', self.count)
        )