<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def encrypt(self, document_id, content, account):
 """ Encrypt string data using the DID as an secret store id, if secret store is enabled then return the result from secret store encryption None for no encryption performed :param document_id: hex str id of document to use for encryption session :param content: str to be encrypted :param account: Account instance encrypting this content :return: hex str encrypted content """

        return self._secret_store(account).encrypt_document(document_id, content)