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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 resolution(self, indicator=None):
 """Update the URI to retrieve host resolutions for the provided indicator. Args: indicator (string):
 The indicator to retrieve resolutions. """

        self._request_entity = 'dnsResolution'
        self._request_uri = '{}/dnsResolutions'.format(self._request_uri)
        if indicator is not None:
            self._request_uri = '{}/{}/dnsResolutions'.format(self._api_uri, indicator)