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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 observed(self, date_observed=None):
 """Retrieve indicator observations count for top 10"""

        if self.name != 'Indicator':
            self.tcex.log.warning(u'Observed endpoint only available for "indicator" endpoint.')
        else:
            self._request_uri = '{}/observed'.format(self._request_uri)
            if date_observed is not None:
                self._request.add_payload('dateObserved', date_observed)