'Lookup a futures contract with a given symbol.
Parameters
symbol : str
The symbol of the desired contract.
Returns
future : Future
The future that trades with the name ``symbol``.
Raises
SymbolNotFound
Raised when no contract named \'symbol\' is found.'

@api_method
@preprocess(symbol=ensure_upper_case)
def future_symbol(self, symbol):

    return self.asset_finder.lookup_future_symbol(symbol)
