Python daily delicious (22)-copy object (deep copy deepcopy and light copy)

Objects in Python are assigned values by reference. To copy objects, use the copy module in the standard library.
1. Copy. Copy: only the parent object is copied, and the internal sub-objects of the object are not copied.
2. Copy. deepcopy: Deep copy object and its sub-objects
A good example: Import Copy
A = [ 1 , 2 , 3 , 4 ,[ ' A ' , ' B ' ] # Original object

B = A # Assign values to pass object references
C = Copy. Copy () # Object copy and shortest copy
D = Copy. deepcopy () # Object copy, deep copy

A. append ( 5 ) # Modify Object
A [ 4 ]. Append ( ' C ' ) # Modify the ['A', 'B'] array object in object

Print   ' A = ' ,
Print   ' B = ' , B
Print   ' C = ' , C
Print   ' D = ' , D

Output result:
A = [1, 2, 3, 4, ['A', 'B', 'C'], 5]
B = [1, 2, 3, 4, ['A', 'B', 'C'], 5]
C = [1, 2, 3, 4, ['A', 'B', 'C']
D = [1, 2, 3, 4, ['A', 'B']

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