Fix typing for py35, remove handlers block from mypy.ini

Author: trsvchn

ignite/handlers/checkpoint.py

@@ -288,7 +288,7 @@ def __init__(
         self.ext = "pt"
         self.global_step_transform = global_step_transform
         self.filename_pattern = filename_pattern
-        self._saved: list = []
+        self._saved = []  # type: list
         self.include_self = include_self
 
     @property

mypy.ini

@@ -11,10 +11,6 @@ ignore_errors = True
 
 ignore_errors = True
 
-[mypy-ignite.handlers.*]
-
-ignore_errors = False
-
 [mypy-ignite.engine.*]
 
 ignore_errors = True