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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:
 def call(self, transaction=None, block_identifier='latest'):
 """ Execute a contract function call using the `eth_call` interface. This method prepares a ``Caller`` object that exposes the contract functions and public variables as callable Python functions. Reading a public ``owner`` address variable example: .. code-block:: python ContractFactory = w3.eth.contract( abi=wallet_contract_definition["abi"] ) # Not a real contract address contract = ContractFactory("0x2f70d3d26829e412A602E83FE8EeBF80255AEeA5") # Read "owner" public variable addr = contract.functions.owner().call() :param transaction: Dictionary of transaction info for web3 interface :return: ``Caller`` object that has contract public functions and variables exposed as Python methods """

        if transaction is None:
            call_transaction = {}
        else:
            call_transaction = dict(**transaction)

        if 'data' in call_transaction:
            raise ValueError("Cannot set data in call transaction")

        if self.address:
            call_transaction.setdefault('to', self.address)
        if self.web3.eth.defaultAccount is not empty:
            call_transaction.setdefault('from', self.web3.eth.defaultAccount)

        if 'to' not in call_transaction:
            if isinstance(self, type):
                raise ValueError(
                    "When using `Contract.[methodtype].[method].call()` from"
                    " a contract factory you "
                    "must provide a `to` address with the transaction"
                )
            else:
                raise ValueError(
                    "Please ensure that this contract instance has an address."
                )

        block_id = parse_block_identifier(self.web3, block_identifier)

        return call_contract_function(
            self.web3,
            self.address,
            self._return_data_normalizers,
            self.function_identifier,
            call_transaction,
            block_id,
            self.contract_abi,
            self.abi,
            *self.args,
            **self.kwargs
        )