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Retrieving Initial Elements from Sublists in Python
To extract the first item from each sublist in a list of lists and store these values in a new list, we employ list comprehension. This powerful technique allows for concise and efficient data manipulation in Python.
Using List Comprehension:
lst2 = [item[0] for item in lst]
In this code snippet, for each item in the original list (lst), we retrieve its first element (index 0) and append it to the new list (lst2).
Example:
Consider the following list of lists:
lst = [['a', 'b', 'c'], [1, 2, 3], ['x', 'y', 'z']]
Using list comprehension, we can effortlessly extract the initial elements of each sublist:
lst2 = [item[0] for item in lst]
This operation results in the creation of a new list lst2 containing the first elements of each sublist:
lst2 = ['a', 1, 'x']
Through list comprehension, we effectively extract the desired elements and generate the desired output.
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