Last Updated : 12 Apr, 2022
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Dictionary in Python is an unordered collection of data values, used to store data values like a map, which unlike other Data Types that hold only a single value as an element, Dictionary holds key: value pair.
Note: has_key() method was removed in Python 3. Use the in operator instead.
In Python Dictionary, has_key() method returns true if specified key is present in the dictionary, else returns false.
Syntax: dict.has_key(key)
Parameters:
- key – This is the Key to be searched in the dictionary.
Returns: Method returns true if a given key is available in the dictionary, otherwise it returns a false.
Example #1:
Python
# Python program to show working
# of has_key() method in Dictionary
# Dictionary with three items
Dictionary1 = {'A': 'Geeks', 'B': 'For', 'C': 'Geeks'}
# Dictionary to be checked
print("Dictionary to be checked: ")
print(Dictionary1)
# Use of has_key() to check
# for presence of a key in Dictionary
print(Dictionary1.has_key('A'))
print(Dictionary1.has_key('For'))
Output:
Dictionary to be checked: {'A': 'Geeks', 'C': 'Geeks', 'B': 'For'}TrueFalseExample #2:
Python
# Python program to show working
# of has_key() method in Dictionary
See Also
W3Schools.com# Dictionary with three items
Dictionary2 = {1: 'Welcome', 2: 'To', 3: 'Geeks'}
# Dictionary to be checked
print("Dictionary to be checked: ")
print(Dictionary2)
# Use of has_key() to check
# for presence of a key in Dictionary
print(Dictionary2.has_key(1))
print(Dictionary2.has_key('To'))
Output:
Dictionary to be checked: {1: 'Welcome', 2: 'To', 3: 'Geeks'}TrueFalseNote : dict.has_key() has removed from Python 3.x
has_key() has been removed in Python 3. in operator is used to check whether a specified key is present or not in a Dictionary.
Example:
Python3
# Python Program to search a key in Dictionary
# Using in operator
dictionary = {1: "Geeks", 2: "For", 3: "Geeks"}
print("Dictionary: {}".format(dictionary))
# Return True if Present.
if 1 in dictionary: # or "dictionary.keys()"
print(dictionary[1])
else:
print("{} is Absent".format(1))
# Return False if not Present.
if 5 in dictionary.keys():
print(dictionary[5])
else:
print("{} is Absent".format(5))
Output:
Dictionary: {1:"Geeks",2:"For",3:"Geeks"}Geeks5 is Absent A
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