code: function(arg, suffix) {
        if (Blockly.isNumber(arg)) {
          // Simple number.
          arg = parseFloat(arg);
        } else if (arg.match(/^\w+$/)) {
          // Variable.
          arg = 'float(' + arg + ')';
        } else {
          // It's complicated.
          var varName = Blockly.Python.variableDB_.getDistinctName(
              variable0 + suffix, Blockly.Variables.NAME_TYPE);
          code += varName + ' = float(' + arg + ')\n';
          arg = varName;
        }
        return arg;
      }
docs: Cache non-trivial values to variables to prevent repeated look-ups.