      https://github.com/1adrianb/face-alignment
  """
  import cv2
  import numpy as np
  
  from lib.model.session import KSession
  from ._base import Aligner, logger
  
 
</s> remove from lib.multithreading import MultiThread
 </s> add from lib.model.session import KSession </s> remove from lib.multithreading import MultiThread
 </s> add from lib.model.session import KSession
import keras
from keras import backend as K
      https://github.com/1adrianb/face-alignment
  """
  import cv2
  import numpy as np
import keras
from keras import backend as K
  
  from lib.model.session import KSession
  from ._base import Aligner, logger
  
keep keep keep add keep keep keep keep
 De-Multiprocess Extract (#871)

* requirements.txt: - Pin opencv to 4.1.1 (fixes cv2-dnn error)

* lib.face_detect.DetectedFace: change LandmarksXY to landmarks_xy. Add left, right, top, bottom attributes

* lib.model.session: Session manager for loading models into different graphs (for Nvidia + CPU)

* plugins.extract._base: New parent class for all extract plugins

* plugins.extract.pipeline. Remove MultiProcessing. Dynamically limit batchsize for Nvidia cards. Remove loglevel input

* S3FD + FAN plugins. Standardise to Keras version for all backends

* Standardize all extract plugins to new threaded codebase

* Documentation. Start implementing Numpy style docstrings for Sphinx Documentation

* Remove s3fd_amd. Change convert OTF to expect DetectedFace object

* faces_detect - clean up and documentation

* Remove PoolProcess

* Migrate manual tool to new extract workflow

* Remove AMD specific extractor code from cli and plugins

* Sort tool to new extract workflow

* Remove multiprocessing from project

* Remove multiprocessing queues from QueueManager

* Remove multiprocessing support from logger

* Move face_filter to new extraction pipeline

* Alignments landmarksXY > landmarks_xy and legacy handling

* Intercept get_backend for sphinx doc build

# Add Sphinx documentation 
plugins/extract/align/fan.py