fixed typo, now correctly check isdir

fixes #3089

files/file.py

@@ -309,7 +309,7 @@ def main():
                         except OSError, ex:
                             # Possibly something else created the dir since the os.path.exists
                             # check above. As long as it's a dir, we don't need to error out.
-                            if not (ex.errno == errno.EEXIST and os.isdir(curpath)):
+                            if not (ex.errno == errno.EEXIST and os.path.isdir(curpath)):
                                 raise
                         tmp_file_args = file_args.copy()
                         tmp_file_args['path']=curpath