Update index.md

update code to account for naming convention change

Author: JohannesSchulz97

src/content/developers/docs/standards/tokens/erc-20/index.md

@@ -125,7 +125,7 @@ simplified_abi = [
     }
 ]
 
-dai_contract = w3.eth.contract(address=w3.toChecksumAddress(dai_token_addr), abi=simplified_abi)
+dai_contract = w3.eth.contract(address=w3.to_checksum_address(dai_token_addr), abi=simplified_abi)
 symbol = dai_contract.functions.symbol().call()
 decimals = dai_contract.functions.decimals().call()
 totalSupply = dai_contract.functions.totalSupply().call() / 10**decimals
@@ -136,7 +136,7 @@ print("===== %s =====" % symbol)
 print("Total Supply:", totalSupply)
 print("Addr Balance:", addr_balance)
 
-weth_contract = w3.eth.contract(address=w3.toChecksumAddress(weth_token_addr), abi=simplified_abi)
+weth_contract = w3.eth.contract(address=w3.to_checksum_address(weth_token_addr), abi=simplified_abi)
 symbol = weth_contract.functions.symbol().call()
 decimals = weth_contract.functions.decimals().call()
 totalSupply = weth_contract.functions.totalSupply().call() / 10**decimals