Blender script to take a list of poses in a pose library and turn them into keyframes

pose_library_to_keyframes.py

import bpy

# Leave this value at 1
start_f_pose_number = 1

# Change this value to the F number of the last pose in your
# pose library action
end_f_pose_number = 106

# *** IMPORTANT ***
# To use this script
# 1. Enter pose mode
# 2. A --> A to select all bones
# 3. Stay in Pose Mode with all bones selected, then run script
armature = bpy.context.object

# Enter the scene name inbetween the ""
# You can see it at the very top right, to the left of RenderLayer
# By default it just says Scene so type that in the ""
scene_name = ""

# This makes it so that wherever you put your current frame marker
# in your timeline is where your animation will be inserted
original_frame = bpy.data.scenes[scene_name].frame_current

for x in range (start_f_pose_number, end_f_pose_number):
    
    y = x - 1
    bpy.types.ActionPoseMarkers.active_index = y
    bpy.data.scenes[scene_name].frame_set(x + original_frame)
    bpy.ops.poseLib.apply_pose(pose_index = y)
    
    for bone in armature.pose.bones:
        bone.keyframe_insert(data_path = "location")
        bone.keyframe_insert(data_path = "scale")
        
        # *** IMPORTANT ***
        # Remove the hashtag symbol in front of the bone.keyframe_insert()
        # line that cooresponds to the type of rotation you're using for each bone
        # and replace with a space
        # Then add a hashtag in front of the one that was previously commented out in gray text
        
        # I'm assuming that you're only using one type of rotation for all bones in your armature
        # since the Valve Biped system uses quaternions
        
        # If your custom rig uses a combination of any of these... you're on your own. This script
        # won't work.
        
        bone.keyframe_insert(data_path = "rotation_quaternion")
      # bone.keyframe_insert(data_path = "rotation_euler")
      # bone.keyframe_insert(data_path = "rotation_axis_angle")