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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:
 async def issuer_create_schema(issuer_did: str, name: str, version: str, attrs: str) -> (str, str):
 """ Create credential schema entity that describes credential attributes list and allows credentials interoperability. Schema is public and intended to be shared with all anoncreds workflow actors usually by publishing SCHEMA transaction to Indy distributed ledger. It is IMPORTANT for current version POST Schema in Ledger and after that GET it from Ledger with correct seq_no to save compatibility with Ledger. After that can call indy_issuer_create_and_store_credential_def to build corresponding Credential Definition. :param issuer_did: DID of schema issuer :param name: a name the schema :param version: a version of the schema :param attrs: a list of schema attributes descriptions (the number of attributes should be less or equal than 125) :return: schema_id: identifier of created schema schema_json: schema as json """


    logger = logging.getLogger(__name__)
    logger.debug("issuer_create_schema: >>> issuer_did: %r, name: %r, version: %r, attrs: %r",
                 issuer_did,
                 name,
                 version,
                 attrs)

    if not hasattr(issuer_create_schema, "cb"):
        logger.debug("issuer_create_schema: Creating callback")
        issuer_create_schema.cb = create_cb(CFUNCTYPE(None, c_int32, c_int32, c_char_p, c_char_p))

    c_issuer_did = c_char_p(issuer_did.encode('utf-8'))
    c_name = c_char_p(name.encode('utf-8'))
    c_version = c_char_p(version.encode('utf-8'))
    c_attrs = c_char_p(attrs.encode('utf-8'))

    (schema_id, schema_json) = await do_call('indy_issuer_create_schema',
                                             c_issuer_did,
                                             c_name,
                                             c_version,
                                             c_attrs,
                                             issuer_create_schema.cb)

    res = (schema_id.decode(), schema_json.decode())
    logger.debug("issuer_create_schema: <<< res: %r", res)
    return res