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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