A script I whipped to automate moving files inside various folders collectively into another master folder. Around 70 GB of data was moved in a couple of minutes.

movefiles.py

import os
import send2trash

source_root = "E:\\storage\\nexus6p"
destination = "E:\\storage\\nexus6p\\allpics"

#to move files from various subfolders to another folder. Takes care of repeated files too
for root, dirs, files in os.walk(source_root):
    print("in {}, moving {} to {}".format(root, files, destination))
    for file in files:
        try:
            os.rename(os.path.join(root, file), os.path.join(destination, file))
        except FileExistsError:
            pass

#The below is to remove empty folders and send them to the recycle bin.
allfolders = os.listdir("E:\\storage\\nexus6p")
for folder in allfolders:
    if os.path.getsize(folder) == 0:
        send2trash.send2trash(folder)