Change cachecontrol library to ensure cache file exists before attempting delete.

CHANGES.md

@@ -59,6 +59,7 @@
 * Update ConfigObj library 4.6.0 to 5.1.0 (a68530a)
 * Update Beautiful Soup to 4.3.2 (r353)
 * Update jsonrpclib library r20 to (b59217c)
+* Change cachecontrol library to ensure cache file exists before attempting delete
 
 [develop changelog]
 * Update Requests library 2.7.0 (ab1f493) to 2.7.0 (8b5e457)

HACKS.txt

@@ -3,3 +3,4 @@ Libs with customisations...
 /tornado
 /lib/requests/packages/urllib3/connectionpool.py
 /lib/requests/packages/urllib3/util/ssl_.py
+/lib/cachecontrol/caches/file_cache.py

lib/cachecontrol/caches/file_cache.py

@@ -90,7 +90,7 @@ class FileCache(BaseCache):
 
     def delete(self, key):
         name = self._fn(key)
-        if not self.forever:
+        if not self.forever and os.path.exists(name):
             os.remove(name)