How do you convert a list to a key value pair in python?

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Given a list, write a Python program to convert the given list to dictionary such that all the odd elements have the key, and even number elements have the value. Since python dictionary is unordered, the output can be in any order.
Examples: 
 

Input : ['a', 1, 'b', 2, 'c', 3]
Output : {'a': 1, 'b': 2, 'c': 3}

Input : ['Delhi', 71, 'Mumbai', 42]
Output : {'Delhi': 71, 'Mumbai': 42}

  
Method #1 : dict comprehension
To convert a list to dictionary, we can use list comprehension and make a key:value pair of consecutive elements. Finally, typecase the list to dict type. 
 

Python3

def Convert[lst]:

    res_dct = {lst[i]: lst[i + 1] for i in range[0, len[lst], 2]}

    return res_dct

lst = ['a', 1, 'b', 2, 'c', 3]

print[Convert[lst]]

Output

{'a': 1, 'b': 2, 'c': 3}

  
Method #2 : Using zip[] method
First create an iterator, and initialize it to variable ‘it’. Then use zip method, to zip keys and values together. Finally typecast it to dict type. 
 

Python3

def Convert[a]:

    it = iter[a]

    res_dct = dict[zip[it, it]]

    return res_dct

lst = ['a', 1, 'b', 2, 'c', 3]

print[Convert[lst]]

Output

{'a': 1, 'b': 2, 'c': 3}

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Given list of elements, convert each element to a key-value pair dictionary, dividing digits equally.

Input : test_list = [2323, 82, 129388, 234, 95] 
Output : {23: 23, 8: 2, 129: 388, 2: 34, 9: 5} 
Explanation : Digits distributed equally to keys and values.

Input : test_list = [2323, 82, 129388] 
Output : {23: 23, 8: 2, 129: 388} 
Explanation : Digits distributed equally to keys and values. 
 

Approach: Using list slicing + loop

In this, we form key-value pair by getting the sliced values from each element by dividing by half the digits for keys and values.

Python3

test_list = [2323, 82, 129388, 234, 95]

print["The original list is : " + str[test_list]]

res = dict[]

for ele in test_list:

    mid_idx = len[str[ele]] // 2

    key = int[str[ele][:mid_idx]]

    val = int[str[ele][mid_idx:]]

    res[key] = val

print["Constructed Dictionary : " + str[res]]

Output

The original list is : [2323, 82, 129388, 234, 95]
Constructed Dictionary : {23: 23, 8: 2, 129: 388, 2: 34, 9: 5}