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# Python | Find all items in a list

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Method # 1: Using List Comprehension + `len()`
We can solve this problem by using list comprehension as a potential shortcut to the usual loops we can be used to accomplish this specific task. We simply iterate over and count the nested list and finally return the cumulative score using the len function.

 ` # Python3 demo code ` ` # count of all items in the list ` ` # Using the comprehension list `   ` # initializing list ` ` test_list ` ` = ` ` [[` ` 1 ` `, ` ` 4 ` `, ` ` 5 ` `], [` ` 7 ` `, ` ` 3 ` ` ], [` ` 4 ` `], [` ` 46 ` `, ` ` 7 ` `, ` ` 3 ` `]] `   ` # print original list ` ` print ` ` (` ` "The original list:" ` ` + ` ` str ` ` ( test_list)) `   ` # using comprehension list ` ` # count of all items in the list ` ` res ` ` = ` ` len ` ` ([ele ` ` for ` ` sub ` ` in ` ` test_list ` ` for ` ` ele ` ` in ` ` sub]) ` ` `  ` # print result ` ` print ` ` (` ` "The total element count in lists is:" ` ` + ` ` str ` ` (res)) `

Output:

` The original list: [[1, 4, 5], [7, 3], [4], [46, 7, 3]] The total element count in lists is: 9 `

Method # 2: Using ` chain () + len () `
This particular the problem can also be solved with a chaining function instead of a list comprehension, in which we use the usual len function to check the length.

 ` # Python3 code to demonstrate walkie talkie ` ` # number of all items in the list ` ` # Using chain () + len () ` ` from ` ` itertools ` ` import ` ` chain `   ` # initializing list ` ` test_list ` ` = ` ` [[` ` 1 ` `, ` ` 4 ` `, ` ` 5 ` `], [` ` 7 ` `, ` ` 3 ` `], [` ` 4 ` `], [` ` 46 ` `, ` ` 7 ` `, ` ` 3 < / code> ]] ``   # print original list print ( "The original list: " + str (test_list))   # using chain () + len () # count of all items in the list res = len ( list (chain ( * test_list)))   # print result print ( "The total element count in lists is:" + str (res)) `

Output:

` The original list: [[1, 4, 5], [7, 3], [4], [46, 7, 3]] The total element count in lists is: 9 `