 # Python | Replace the tuple according to the Nth element of the tuple

Method # 1: Using loop + `enumerate()`
This task can be accomplished using a combination of loops and an enumeration function that can help access Nth element and then check and replace when the condition is met.

 ` # Python3 code to demonstrate how it works ` ` # Replace the tuple according to the Nth element of the tuple ` ` # Using loops + enumerate () `   ` # Initializing list ` ` test_list ` ` = ` ` [(` ` `gfg` ` `, ` ` 1 ` `), (` `` was` ` , ` 2 ` `), (` ` `best` ` `, ` ` 3 ` `)] `   ` # print original list ` ` print ` ` (` ` "The original list is:" ` ` + ` ` str ` ` (test_list)) `   ` # Initialize change recording ` ` repl_rec ` ` = ( `is` , 2 ) ````   # Initializing N N = 1   # Replace the tuple according to the Nth element of the tuple # Using loops + enumerate () for key, val in enumerate (test_list): if val [N] = = repl_rec [N]: test_list [key] = repl_rec   break    # print result print ( "The tuple after replacement is:" + str (test_list) ) ```

Output:

` The original list is: [(`gfg`, 1), (` was`, 2), (`best`, 3)] The tuple after replacement is: [(` gfg`, 1), (`is`, 2) , (`best`, 3)] `

Method # 2: Using List Comprehension
This is a one-line approach to solve this particular problem. In this we simply iterate over the list element and continue matching the corresponding Nth element of the tuple and performing the replacement.

 ` # Python3 code to demonstrate how it works ` ` # Replace the tuple according to the Nth element of the tuple ` ` # Using the comprehension list `   ` # Initializing list ` ` test_list ` ` = ` ` [(` ` `gfg` ` `, ` ` 1 ` `), (` ` `was` ` `, ` ` 2 ` `), (` ` `best` ` `, ` ` 3 ` `)] `   ` # print the original list ` ` print ` ` (` ` " The original list is: "` ` + ` ` str ` ` (test_list)) `   ` # Initialize a change record ` ` repl_rec ` ` = ` ` (` ` `is` ` `, ` ` 2 ` `) `   ` # Initialization N ` ` N = 1 ````   # Replace with rte according to the Nth element of the tuple # Using the comprehension list res = [repl_rec if sub [N] = = repl_rec [N] else sub for sub in test_list]   # print result print ( "The tuple after replacement is:" + str (res)) ```

Output:

` The origina l list is: [(`gfg`, 1), (` was`, 2), (`best`, 3)] The tuple after replacement is: [(` gfg`, 1), (`is`, 2 ), (`best`, 3)] `