we are going to take the 0 th element of each row
the row we are considering : [1, 2, 3, 4] and we are going to add 1 to a temporary list
the row we are considering : [2, 3, 4, 5] and we are going to add 2 to a temporary list
the row we are considering : [3, 4, 5, 6] and we are going to add 3 to a temporary list
the 0 th column elements = 0 th elements in every row are = [1, 2, 3]
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we are going to take the 1 th element of each row
the row we are considering : [1, 2, 3, 4] and we are going to add 2 to a temporary list
the row we are considering : [2, 3, 4, 5] and we are going to add 3 to a temporary list
the row we are considering : [3, 4, 5, 6] and we are going to add 4 to a temporary list
the 1 th column elements = 1 th elements in every row are = [2, 3, 4]
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we are going to take the 2 th element of each row
the row we are considering : [1, 2, 3, 4] and we are going to add 3 to a temporary list
the row we are considering : [2, 3, 4, 5] and we are going to add 4 to a temporary list
the row we are considering : [3, 4, 5, 6] and we are going to add 5 to a temporary list
the 2 th column elements = 2 th elements in every row are = [3, 4, 5]
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we are going to take the 3 th element of each row
the row we are considering : [1, 2, 3, 4] and we are going to add 4 to a temporary list
the row we are considering : [2, 3, 4, 5] and we are going to add 5 to a temporary list
the row we are considering : [3, 4, 5, 6] and we are going to add 6 to a temporary list
the 3 th column elements = 3 th elements in every row are = [4, 5, 6]
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[[1, 2, 3], [2, 3, 4], [3, 4, 5], [4, 5, 6]]