Cannot instantiate a chaincode - AttributeError: 'NoneType' object has no attribute 'send_instantiate_proposal'

[IIRobotNinjaII]

import asyncio
from hfc.fabric import Client

loop = asyncio.get_event_loop()
cli = Client(net_profile="test/fixtures/network.json")
org1_admin = cli.get_user('org1.example.com', 'Admin')

import os
gopath_bak = os.environ.get('GOPATH', '/usr/local/go')
gopath = os.path.normpath(os.path.join(
                      os.path.dirname(os.path.realpath('__file__')),
                      'test/fixtures/chaincode'
                     ))
os.environ['GOPATH'] = os.path.abspath(gopath)

#The response should be true if succeed
responses = loop.run_until_complete(cli.chaincode_install(
               requestor=org1_admin,
               peers=['peer0.org1.example.com',
                      'peer1.org1.example.com'],
               cc_path='github.com/example_cc',
               cc_name='example_cc',
               cc_version='v1.0'
               ))
print(responses,"Chaincode Installed")
Instantiate Chaincode in Channel, the response should be true if succeed
args = ['a', '200', 'b', '300']

# policy, see https://hyperledger-fabric.readthedocs.io/en/release-1.4/endorsement-policies.html
policy = {
    'identities': [
        {'role': {'name': 'member', 'mspId': 'Org1MSP'}},
    ],
    'policy': {
        '1-of': [
            {'signed-by': 0},
        ]
    }
}
response = loop.run_until_complete(cli.chaincode_instantiate(
               requestor=org1_admin,
               channel_name='businesschannel',
               peers=['peer0.org1.example.com'],
               args=args,
               cc_name='example_cc',
               cc_version='v1.0',               
               cc_endorsement_policy=policy, # optional, but recommended
               collections_config=None, # optional, for private data policy
               transient_map=None, # optional, for private data
               wait_for_event=True # optional, for being sure chaincode is instantiated
               ))
print('Chainode Instantiated Response : ',response)

Get the following error

  File "trial.py", line 97, in <module>
    wait_for_event=True # optional, for being sure chaincode is instantiated
  File "/home/antony/.pyenv/versions/3.7-dev/lib/python3.7/asyncio/base_events.py", line 587, in run_until_complete
    return future.result()
  File "/home/antony/abe/fabric-sdk-py/hfc/fabric/client.py", line 1214, in chaincode_instantiate
    cc_type=cc_type)
  File "/home/antony/abe/fabric-sdk-py/hfc/fabric/chaincode.py", line 134, in instantiate
    cc_type=cc_type)
  File "/home/antony/abe/fabric-sdk-py/hfc/fabric/chaincode.py", line 233, in _instantiate_or_upgrade
    tx_context_dep, target_peers, channel)
  File "/home/antony/abe/fabric-sdk-py/hfc/fabric/chaincode.py", line 53, in send_instantiate_proposal
    return channel.send_instantiate_proposal(tx_context, peers)
AttributeError: 'NoneType' object has no attribute 'send_instantiate_proposal'