some renames and organization in getenv()

Author: glaukiol1

os/os.module.go

@@ -98,9 +98,9 @@ func chdir(self py.Object, args py.Tuple) (py.Object, error) {
 // If no such environment variable exists and a default value was provided, that value is returned.
 func getenv(self py.Object, args py.Tuple) (py.Object, error) {
 	var (
-		key py.Object
-		dflt = py.None
-		err error
+		key  py.Object
+		dflt py.Object = py.None
+		err  error
 	)
 
 	if len(args) == 1 {
@@ -109,7 +109,7 @@ func getenv(self py.Object, args py.Tuple) (py.Object, error) {
 		} else {
 			return nil, py.ExceptionNewf(py.TypeError, "str expected (pos 1), not "+args[0].Type().Name)
 		}
-		default_ = py.None
+		dflt = py.None
 	} else if len(args) == 2 {
 		if objectIsString(args[0]) {
 			key = args[0]
@@ -118,7 +118,7 @@ func getenv(self py.Object, args py.Tuple) (py.Object, error) {
 		}
 		if objectIsString(args[1]) {
 			key = args[0]
-			default_ = args[1]
+			dflt = args[1]
 		} else {
 			return nil, py.ExceptionNewf(py.TypeError, "str expected (pos 2), not"+args[1].Type().Name)
 		}
@@ -128,7 +128,7 @@ func getenv(self py.Object, args py.Tuple) (py.Object, error) {
 	var res py.Object // hold the result value
 	res, err = getEnvVariables().M__getitem__(key)
 	if err != nil {
-		return default_, nil
+		return dflt, nil
 	}
 	return res, nil
 }