AttributeError: 'NoneType' object has no attribute 'get_type_string'

[klemendrobnic]

I would need help with resolving an error that occurs when im trying to use compose_call function.

from substrateinterface import SubstrateInterface

substrate = SubstrateInterface(url="wss://ws.framenode-7.s4.stg1.sora2.soramitsu.co.jp")


call = substrate.compose_call(call_module='Balances',call_function='transfer',call_params={'dest': '5CvxUr1gXDvAN8qEDPBFVdnF7QcPwNfYCQLYDDr3cCzC45Vt','value': 1 * 10**12})

I get the following error:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/klemendrobnic/.local/lib/python3.10/site-packages/substrateinterface/base.py", line 1408, in compose_call
    call.encode({
  File "/home/klemendrobnic/.local/lib/python3.10/site-packages/scalecodec/base.py", line 929, in encode
    self.data = self.process_encode(self.value_serialized)
  File "/home/klemendrobnic/.local/lib/python3.10/site-packages/scalecodec/types.py", line 1652, in process_encode
    call_type_string = self.call_module['calls'].value_object.get_type_string()
AttributeError: 'NoneType' object has no attribute 'get_type_string'

When i print the call_module that is called in the process_encode method i get the object printed, however the parameter calls is not included (call_type_string = self.call_module['calls'].value_object.get_type_string()) -> the code fails here
Thanks for any suggestions

[arjanz]

After examining the metadata of the runtime, I found out that the Balances pallet for the endpoint you provided has in fact no runtime calls at all (so call transfer couldn't be found). You can also check PolkadotJS

However, the error handler could be improved here, the current thrown exception is indeed confusing and should be something like Call function 'transfer' not found. I'll make an issue for this.

[klemendrobnic]

The solution here was that the call_module=Balances, therefore the Balances pallet doesn't exist on the node that I was trying to connect to - Sora network. The solution was to replace the call_module to call_module=Assets and now it works. Thank you for your reply.