fit to paddle2.1 (#995)

Author: wuyefeilin

paddleseg/models/layers/activation.py

@@ -53,14 +53,15 @@ def __init__(self, act=None):
         super(Activation, self).__init__()
 
         self._act = act
-        upper_act_names = nn.layer.activation.__all__
+        upper_act_names = nn.layer.activation.__dict__.keys()
         lower_act_names = [act.lower() for act in upper_act_names]
         act_dict = dict(zip(lower_act_names, upper_act_names))
 
         if act is not None:
             if act in act_dict.keys():
                 act_name = act_dict[act]
-                self.act_func = eval("nn.layer.activation.{}()".format(act_name))
+                self.act_func = eval(
+                    "nn.layer.activation.{}()".format(act_name))
             else:
                 raise KeyError("{} does not exist in the current {}".format(
                     act, act_dict.keys()))