import os
import posixpath
import shutil
mydict = {}

directory = os.walk('/home/ec2-user/backup')
root = '/home/ec2-user/'

for item in directory:
  maindir,subdir,files = item
  for file in files:
    abspath = posixpath.join(maindir,file)
    *_,x = posixpath.splitext(abspath)
    ext = x.lstrip(".")
    if ext not in mydict:
      mydict[ext] = [abspath]
    else:
      mydict[ext].append(abspath)

for item in mydict:
  if not os.path.exists(posixpath.join(root,item)):
    os.mkdir(posixpath.join(root,item))
  for new in mydict[item]:
    shutil.copy(new,(posixpath.join(root,item)))