Python | Initialize a dictionary with only keys from a list
Given a List, the task is to create a dictionary with only keys by using given list as keys.
Let’s see the different methods we can do this task.
Method #1 : By iterating through list
# Python code to initialize a dictionary # with only keys from a list # List of keys keyList = [ "Paras" , "Jain" , "Cyware" ] # initialize dictionary d = {} # iterating through the elements of list for i in keyList: d[i] = None print (d) |
Output:
{'Cyware': None, 'Paras': None, 'Jain': None}
Method #2 : Using dictionary comprehension
# Python code to initialize a dictionary # with only keys from a list # List of Keys keyList = [ "Paras" , "Jain" , "Cyware" ] # Using Dictionary comprehension myDict = {key: None for key in keyList} print (myDict) |
Output:
{'Paras': None, 'Jain': None, 'Cyware': None}
Method #3 : Using zip() function
# Python code to initialize a dictionary # with only keys from a list # List of keys listKeys = [ "Paras" , "Jain" , "Cyware" ] # using zip() function to create a dictionary # with keys and same length None value dct = dict ( zip (listKeys, [ None ] * len (listKeys))) # print dict print (dct) |
Output:
{'Cyware': None, 'Paras': None, 'Jain': None}
Method #4 : Using fromkeys() method
# Python code to initialize a dictionary # with only keys from a list # List of keys Student = [ "Paras" , "Jain" , "Cyware" ] # using fromkeys() method StudentDict = dict .fromkeys(Student, None ) # printing dictionary print (StudentDict) |
Output:
{'Cyware': None, 'Jain': None, 'Paras': None}
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