diff --git a/input_readers.py b/input_readers.py
index aab06df..6dcc28d 100644
--- a/input_readers.py
+++ b/input_readers.py
@@ -22,8 +22,7 @@
 @author:  cloudysunny14@gmail.com
 '''
 import logging
-
-from mapreduce.lib import files
+import cloudstorage
 from mapreduce import input_readers
 from mapreduce import errors
 
@@ -87,6 +86,7 @@ def validate(cls, mapper_spec):
 
     params = _get_params(mapper_spec)
 
+    # import pdb; pdb.set_trace()
     if cls.FILE_PATHS_PARAM not in params:
       raise BadReaderParamsError("Must specify 'file_path' for mapper input")
 
@@ -126,9 +126,8 @@ def split_input(cls, mapper_spec):
     file_sizes = {}
 
     for file_path in file_paths:
-      fp = files.BufferedFile(file_path)
-      fp.seek(0, 2)
-      file_sizes[file_path] = fp.tell()
+      fstat = cloudstorage.stat(file_path)
+      file_sizes[file_path] = fstat.st_size
 
     shard_count = min(cls._MAX_SHARD_COUNT, mapper_spec.shard_count)
     shards_per_file = shard_count // len(file_paths)
@@ -157,7 +156,7 @@ def next(self):
     self._has_iterated = True
 
     if not self._filestream:
-      self._filestream = files.BufferedFile(self._file_path)
+      self._filestream = cloudstorage.open(self._file_path)
       if self._start_position:
         self._filestream.seek(self._start_position)
         self._filestream.readline()