[Python] Replace values in a list of dictionaries using for loop [duplicate]

I have the following simple program.

params = {'a':1, 'b':2, 'c':3}

params_array = [params]*10

for i in range(len(params_array)):
params_array['a'] = i
print(params_array)

print(params_array)



The params_array initially looks like this:

[{'a': 1, 'b': 2, 'c': 3}, {'a': 1, 'b': 2, 'c': 3}, {'a': 1, 'b': 2, 'c': 3}, {'a': 1, 'b': 2, 'c': 3}, {'a': 1, 'b': 2, 'c': 3}, {'a': 1, 'b': 2, 'c': 3}, {'a': 1, 'b': 2, 'c': 3}, {'a': 1, 'b': 2, 'c': 3}, {'a': 1, 'b': 2, 'c': 3}, {'a': 1, 'b': 2, 'c': 3}]


Each element of the array gets updated correctly within each iteration of the for loop:

{'a': 0, 'b': 2, 'c': 3}
{'a': 1, 'b': 2, 'c': 3}
{'a': 2, 'b': 2, 'c': 3}
{'a': 3, 'b': 2, 'c': 3}
{'a': 4, 'b': 2, 'c': 3}
{'a': 5, 'b': 2, 'c': 3}
{'a': 6, 'b': 2, 'c': 3}
{'a': 7, 'b': 2, 'c': 3}
{'a': 8, 'b': 2, 'c': 3}
{'a': 9, 'b': 2, 'c': 3}


But the params_array that comes out of the for loop has all the values replaced with the last value.

[{'a': 9, 'b': 2, 'c': 3}, {'a': 9, 'b': 2, 'c': 3}, {'a': 9, 'b': 2, 'c': 3}, {'a': 9, 'b': 2, 'c': 3}, {'a': 9, 'b': 2, 'c': 3}, {'a': 9, 'b': 2, 'c': 3}, {'a': 9, 'b': 2, 'c': 3}, {'a': 9, 'b': 2, 'c': 3}, {'a': 9, 'b': 2, 'c': 3}, {'a': 9, 'b': 2, 'c': 3}]


What am I doing wrong? Is it a variable scope issue? I thought this method is pretty standard, but I'm not getting the result I expected.

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