Remove MAJOR, MINOR, PATCH and add comment for assert

python/setup.py.in

@@ -18,7 +18,8 @@ def git_commit():
     return git_commit
 
 def _get_version_detail(idx):
-    assert idx < 3
+    assert idx < 3, "vesion info consists of %(major)d.%(minor)d.%(patch)d, \
+        so detail index must less than 3"
 
     version_details = '@PADDLE_VERSION@'.split('.')
     if len(version_details) == 3:
@@ -32,21 +33,21 @@ def get_major():
     if major is not None:
         return major
 
-    return MAJOR
+    return 0
 
 def get_minor():
     minor = _get_version_detail(1)
     if minor is not None:
         return minor
 
-    return MINOR
+    return 0
 
 def get_patch():
     patch = _get_version_detail(2)
     if patch is not None:
         return patch
 
-    return PATCH
+    return 0
 
 def is_taged():
     try: