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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 insert(self, data):
 """ Inserts item into this collection. An _id field will be generated if not assigned in the data. :param data: Document to insert :type data: ``string`` :return: _id of inserted object :rtype: ``dict`` """

        return json.loads(self._post('', headers=KVStoreCollectionData.JSON_HEADER, body=data).body.read().decode('utf-8'))