def contract(nonce, gasprice, startgas, endowment, code, v=0, r=0, s=0):
 tx = Transaction(nonce, gasprice, startgas, '', endowment, code, v, r, s)
 return tx

def contract ( nonce , gasprice , startgas , endowment , code , v = 0 , r = 0 , s = 0 ) : tx = Transaction ( nonce , gasprice , startgas , '' , endowment , code , v , r , s ) return tx
a contract is a special transaction without the to argument .