How to use dictionary {}

What is a dictionary type?

{"a":1,"b":2,"c":3} This time  a,b,c→key  1,2,3→value Say.

Extract dictionary type elements

ta=df["a"]
>>>print(ta)

Execution result


>>>1

Use key to retrieve element (value) like this

Change dictionary type key

df["a"]=4
>>>print(df)

Reference result


>>>{"a":4,"b":2,"c":3}

Same as how to retrieve elements

Add key and value to dictionary type

df.setdefault("d",4)
>>>print(df)

Execution result


>>>{"a":1,"b":2,"c":3,"d":4}

You can add it by using setdefault (key, value) like this.

How to delete dictionary key and value

df.pop("d")
>>>print(df)

Execution result


>>>{"a":1,"b":2,"c":3}

You can delete it by using pop (key) like this

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