old_contents: import copy
  
  a = [1,2,3]
  b = a
  b[1]=22
  print(a)
  print(id(a) == id(b))
  
  # deep copy
  c = copy.deepcopy(a)
  print(id(a) == id(c))
  c[1] = 2
  print(a)
  a[1] = 111
  print(c)
  
  # shallow copy
  a = [1,2,[3,4]]
  d = copy.copy(a)
  print(id(a) == id(d))
  print(id(a[2]) == id(d[2]))
new_contents: # View more python learning tutorial on my Youtube and Youku channel!!!
  
  # Youtube video tutorial: https://www.youtube.com/channel/UCdyjiB5H8Pu7aDTNVXTTpcg
  # Youku video tutorial: http://i.youku.com/pythontutorial
  
  import copy
  
  a = [1,2,3]
  b = a
  b[1]=22
  print(a)
  print(id(a) == id(b))
  
  # deep copy
  c = copy.deepcopy(a)
  print(id(a) == id(c))
  c[1] = 2
  print(a)
  a[1] = 111
  print(c)
  
  # shallow copy
  a = [1,2,[3,4]]
  d = copy.copy(a)
  print(id(a) == id(d))
  print(id(a[2]) == id(d[2]))
  
subject: Update 30_copy_deepcopy.py