Detailed explanation of Python list (List) operation methods

List is the most basic data structure in Python. List is the most commonly used Python data type. The data items of the list do not need to be of the same type. Each element in the list is assigned a number - its position, or index, with the first index being 0, the second index being 1, and so on.
Python has 6 built-in types for sequences, but the most common are lists and tuples. Operations that can be performed on sequences include indexing, slicing, adding, multiplying, and checking members. In addition, Python has built-in methods for determining the length of a sequence and determining the largest and smallest elements.

1. Create a list
Just enclose the different data items separated by commas in square brackets. It looks like this:

list1 = ['physics', 'chemistry', 1997, 2000];
list2 = [1, 2, 3, 4, 5 ];
list3 = ["a", "b", "c", "d"];

Like the indexing of strings, list indexing starts from 0. Lists can be intercepted, combined, etc.
2. Access the values ​​in the list
Use subscript index to access the values ​​in the list. You can also use square brackets to intercept characters, as shown below:

#!/usr/bin/python

list1 = ['physics', 'chemistry', 1997, 2000];
list2 = [1, 2, 3, 4, 5, 6, 7 ];
print "list1[0]: ", list1[0]
print "list2[1:5]: ", list2[1:5]

Output of the above example Result:

list1[0]:  physics
list2[1:5]:  [2, 3, 4, 5]

3. Update the list
You can modify or update the data items of the list. You can also use the append() method to add list items, as shown below:

#!/usr/bin/python
list = ['physics', 'chemistry', 1997, 2000];
print "Value available at index 2 : "
print list[2];
list[2] = 2001;
print "New value available at index 2 : "
print list[2];

Output result of the above example:

Value available at index 2 :
1997
New value available at index 2 :
2001

IV. Delete list elements
You can use the del statement to delete elements of the list, as shown in the following example:

#!/usr/bin/python
list1 = ['physics', 'chemistry', 1997, 2000];
print list1;
del list1[2];
print "After deleting value at index 2 : "
print list1;

Output result of the above example:

['physics', 'chemistry', 1997, 2000]
After deleting value at index 2 :
['physics', 'chemistry', 2000]

L = ['spam', 'Spam', 'SPAM!']