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Creating Dictionaries

List Comprehensions to Dictionaries

Let’s say we have two lists that we want to combine into a dictionary, like a list of students and a list of their heights, in inches:

names = ['Jenny', 'Alexus', 'Sam', 'Grace']
heights = [61, 70, 67, 64]

Python allows you to create a dictionary using a list comprehension, with this syntax:

students = {key:value for key, value in zip(names, heights)}
#students is now {'Jenny': 61, 'Alexus': 70, 'Sam': 67, 'Grace': 64}

Remember that zip() combines two lists into a zipped list of pairs. This list comprehension:

Takes a pair from the zipped list of pairs from names and heights
Names the elements in the pair key (the one originally from the names list) and value (the one originally from the heights list)
Creates a key : value item in the students dictionary
Repeats steps 1-3 for the entire list of pairs

Instructions

You have two lists, representing some drinks sold at a coffee shop and the milligrams of caffeine in each. First, create a variable called zipped_drinks that is a zipped list of pairs between the drinks list and the caffeine list.

Create a dictionary called drinks_to_caffeine by using a list comprehension that goes through the zipped_drinks list and turns each pair into a key:value item.

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