Api update

merge request so that you can comment the code ;)

km3io/aanet.py

@@ -102,7 +102,7 @@ class Reader(AanetKeys):
             path-like object that points to the file of ineterst.
         """
         super().__init__(file_path)
-        self._lazy_data = uproot.open(self._file_path)['E'].lazyarrays()
+        self._data = uproot.open(self._file_path)['E'].lazyarrays()
 
     def __getitem__(self, key):
         """reads data stored in the branch of interest in an event tree.
@@ -268,7 +268,7 @@ class AanetHits:
     def __str__(self):
         # hits
         if all(key.startswith('hits.') for key in self._keys):
-            return "Number of hits in the selected event: {}".format(len(self))
+            return "Number of hits: {}".format(len(self))
         # mc hits
         if all(key.startswith('mc_hits.') for key in self._keys):
             return "Number of mc hits in the selected event: {}".format(