Merge "Add comment and fix on functions that contains bugs in pdp module"

diff --cc python_moondb/python_moondb/api/pdp.py
index c75040a,07feab7..d39418b
--- 1/python_moondb/python_moondb/api/pdp.py
--- 2/python_moondb/python_moondb/api/pdp.py
+++ b/python_moondb/python_moondb/api/pdp.py
@@@ -4,12 -4,12 +4,12 @@@
  # or at 'http://www.apache.org/licenses/LICENSE-2.0'.
  
  from uuid import uuid4
 -from oslo_log import log as logging
 -from python_moonutilities.security_functions import filter_input, enforce
 +import logging
 +from python_moonutilities.security_functions import enforce
  from python_moondb.api.managers import Managers
- 
+ from python_moonutilities import exceptions
  
 -LOG = logging.getLogger("moon.db.api.pdp")
 +logger = logging.getLogger("moon.db.api.pdp")
  
  
  class PDPManager(Managers):