Hopefully fixed import errors on python 2

Author: Sylvain MARIE

mini_lambda/base.py

@@ -1,8 +1,10 @@
 from inspect import isclass
 
-from typing import Callable, Any, Tuple, Union, TypeVar
-
-T = TypeVar('T')
+try:  # python 3.5+
+    from typing import Callable, Any, Tuple, Union, TypeVar
+    T = TypeVar('T')
+except ImportError:
+    pass
 
 # see https://docs.python.org/3/reference/expressions.html#operator-precedence
 from copy import copy

mini_lambda/goodies.py

@@ -1,5 +1,3 @@
-from typing import Callable
-
 from mini_lambda.main import InputVar
 
 # ******* Useful input variables ***********
@@ -19,4 +17,8 @@
 d = InputVar('d', dict)
 
 # callables
-f = InputVar('f', Callable)
+try:
+    from typing import Callable
+    f = InputVar('f', Callable)
+except ImportError:
+    pass