“This is the 25th day of my participation in the Gwen Challenge in November. See details: The Last Gwen Challenge in 2021”

Access the dictionary:

Stage 1: Base operation not 6!

If you want to retrieve the value of a key in the dictionary, you can display the corresponding value by accessing the key. The code:

dict = {'line generation': "99"."Data analysis": "99"."Probability theory": "98"}      # create a dictionary


print('Xiao Hong's line score is:'.dict['line generation'])                  # Output line generation results
print('Xiao Hong's line score is:'.dict['Data analysis'])               # Output data analysis results
print('Xiao Hong's line score is:'.dict['Probability theory'])                # Output probability theory grade

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Stage 2: Common projects!

(1) get gets the value of the specified key, or none if the key does not exist.

The code:

a = {'dry': 11.'age': 11}
print(a.get('age'))
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(2) keys select all keys from the dictionary.

The code:

a = {'dry': 11.'age': 11}
print(a.keys())
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(3) values();The code:

a = {'dry': 11.'age': 11}
print(a.values())
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(4) items fetch all key-value pairs — usage: dictionary name. Items ()

The code:

a = {'dry': 11.'age': 11}
print(a.items())
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(5) setdefault(key) check if there is this key, if there is no increase!

The code:

di2 = {'name':'dry'.'age':18.'sex':'male'}
print(di2.setdefault('name'))
di2.setdefault('name2')
print(di2)
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Have you noticed that this dictionary is different from that one, but it does have some things in common? For example: we look up the dictionary, is to look up a word, and then will find out the meaning of the word and a series of information; The dictionary we use now, if we want to look up the value of a key, also by looking up the key of the way to display the corresponding value! Think deeply, everybody!

Extension: What if we want to look up the value of a key pair that does not exist in the dictionary?

The answer is obvious — there will definitely be an error after execution, but we’re just going to see what kind of error this will report! Is stubborn!!

dict = {'line generation': "99"."Data analysis": "99"."Probability theory": "98"}      # create a dictionary

print(Dict [' language score ']:".dict['Language Results'])
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🔆 In The End!

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