m1n1.utils: Fix len() overflow in RangeMap

This is to fix

  OverflowError: Python int too large to convert to C ssize_t

in case the upper bound of a range is 1<<64.

Signed-off-by: Martin Povišer <[email protected]>

Author: povik

proxyclient/m1n1/utils.py

@@ -519,7 +519,7 @@ def items(self):
 
     def _overlap_range(self, zone, split=False):
         zone = self.__zone(zone)
-        if len(zone) == 0:
+        if not zone:
             return 0, 0
 
         start = bisect.bisect_left(self.__end, zone.start)