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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 releaseLicense(self, username):
 """ If a user checks out an ArcGIS Pro license for offline or disconnected use, this operation releases the license for the specified account. A license can only be used with a single device running ArcGIS Pro. To check in the license, a valid access token and refresh token is required. If the refresh token for the device is lost, damaged, corrupted, or formatted, the user will not be able to check in the license. This prevents the user from logging in to ArcGIS Pro from any other device. As an administrator, you can release the license. This frees the outstanding license and allows the user to check out a new license or use ArcGIS Pro in a connected environment. Parameters: username - username of the account """

        url = self._url + "/licenses/releaseLicense"
        params = {
            "username" : username,
            "f" : "json"
        }
        return self._post(url=url,
                          param_dict=params,
                          proxy_url=self._proxy_url,
                          proxy_port=self._proxy_port)