How to check if a key exists in a dictionary python

Python dictionary is used to store value as key value pair, unlike python list value inside a dictionary can be accessed using the key.

Simple Python Dictionary Example

d = {"one": 10, "two": 22, "three": 28}
print(d["two"]) # Output: 22

when we try to access a key value from dictionary which is not in the variable then it will throw a exception.

d = {"one": 10, "two": 22, "three": 28}
print(d["five"]) 

Error:
Traceback (most recent call last):
File "<string>", line 2, in <module>
KeyError: 'five'

Check if a key exists or not in a dict

To avoid this we can use the python in membership operator to check whether the key is in the dict or not

d = {"one": 10, "two": 22, "three": 28}
print("one" in d)
print("five" in d)

Output:
True
False

by checking the key is in or not will help us to avoid keyerror.

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