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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 delete(self, key):
 """ When applications are provided, this endpoint will remove those applications from the label. When no applications are provided, this endpoint will remove the label. :type key: str :param key: Label key. Example: 'Language:Java' :rtype: dict :return: The JSON response of the API :: { "label": { "key": "string", "category": "string", "name": "string", "links": { "applications": [ "integer" ], "servers": [ "integer" ] } } } """

        return self._delete(
            url='{url}labels/labels/{key}.json'.format(
                url=self.URL,
                key=key),
            headers=self.headers,
        )