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How to convert a list of strings to uppercase in Python

How to convert a list of strings to uppercase in Python.

Here's a step-by-step tutorial on how to convert a list of strings to uppercase in Python.

Step 1: Create a list of strings​

First, you need to create a list of strings that you want to convert to uppercase. You can define the list using square brackets [] and separate each string with a comma. For example:

my_list = ["hello", "world", "python"]

Step 2: Use a for loop to iterate through the list​

Next, you'll use a for loop to iterate through each string in the list. This will allow you to access and modify each string individually. For example:

for i in range(len(my_list)):

Step 3: Convert each string to uppercase​

Inside the for loop, you can use the upper() method to convert each string to uppercase. This method returns a new string with all uppercase characters. For example:

    my_list[i] = my_list[i].upper()

In this example, my_list[i] represents the current string being processed, and .upper() converts it to uppercase.

Step 4: Print or use the modified list​

After converting all the strings to uppercase, you can either print the modified list or use it for further processing. For example:

print(my_list)

This will output the modified list:

["HELLO", "WORLD", "PYTHON"]

Alternatively, you can use the modified list in other parts of your code as needed.

Step 5: Alternative method using list comprehension​

Another way to convert a list of strings to uppercase in Python is by using list comprehension. List comprehension provides a concise way to create and modify lists in a single line of code.

Here's an example using list comprehension to convert a list of strings to uppercase:

my_list = ["hello", "world", "python"]
my_list = [string.upper() for string in my_list]
print(my_list)

This will produce the same output as before:

["HELLO", "WORLD", "PYTHON"]

In this example, [string.upper() for string in my_list] creates a new list by applying the .upper() method to each string in the original list.

That's it! You've now learned how to convert a list of strings to uppercase in Python using both a for loop and list comprehension.