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Loops
More List Comprehensions

Let’s say we’re working with the `usernames` list from the last exercise:

``````>>> print(usernames)
["@coolguy35", "@kewldawg54", "@matchamom"]``````

We want to create a new list with the string `" please follow me!"` added to the end of each `username`. We want to call this new list `messages`. We can use a list comprehension to make this list with one line:

``messages = [user + " please follow me!" for user in usernames]``

This list comprehension:

1. Takes a string in `usernames`
2. Assigns that string to a variable called `user`
3. Adds “ please follow me!” to `user`
4. Appends that concatenation to the new list called `messages`
5. Repeats steps 1-4 for all of the strings in `usernames`

Now, `messages` contains these values:

``["@coolguy35 please follow me!", "@kewldawg54 please follow me!", "@matchamom please follow me!"]``

Being able to create lists with modified values is especially useful when working with numbers. Let’s say we have this list:

``my_upvotes = [192, 34, 22, 175, 75, 101, 97]``

We want to add `100` to each value. We can accomplish this goal in one line:

``updated_upvotes = [vote_value + 100 for vote_value in my_upvotes]``

This list comprehension:

1. Takes a number in `my_upvotes`
2. Assigns that number to a variable called `vote_value`
3. Adds 100 to `vote_value`
4. Appends that sum to the new list `updated_upvotes`
5. Repeats steps 1-4 for all of the numbers in `my_upvotes`

Now, `updated_upvotes` contains these values:

``[292, 134, 122, 275, 175, 201, 197]``

Instructions

1.

We have provided a list of temperatures in celsius. Using a list comprehension, create a new list called `fahrenheit` that converts each element in the `celsius` list to fahrenheit.

*Note: * To convert, use the formula:

``temperature_in_fahrenheit = temperature_in_celsius * 9/5 + 32``
2.

Print `fahrenheit`.