Python Projects for Beginners a ten-Week Bootcamp Approach to Python Programming

Lists with Dictionaries

The combination of lists within dictionaries and vice-versa can become confusing when trying to figure out how to access information. Always remember lists are indexed, and dictionaries use keys. Depending on the order of the data stored, you’ll need to do one or the other first. When a list is storing a dictionary, you need to access that dictionary by the index first. After that you have access to the key-value pairs within the dictionary. Let’s see an example:

# storing a dictionary within a list and accessing it data = [ "John", "Dennis", { "name": "Kirsten" } ] print( data[2] ) # the dictionary is in index 2 print( data[2]["name"] ) # first access the index, then access the key

Go ahead and run the cell. First, we access the item in the second index, which is our dictionary. Then we access the value stored at the “name” key, which is the output of “Kirsten”.
Note Be very careful when using numbers for keys.

Dictionaries with Dictionaries

Dictionaries are very powerful and efficient due to how they’re stored in memory. Often, you’ll want to use dictionaries as the value for your key-value pairs. Let’s see an example:

# storing a dictionary within a dictionary and accessing it data = {
"team": "Boston Red Sox",
"wins": { "2018": 108, "2017": 93 }
}
print( data["wins"] ) # will output the dictionary within the wins key print( data["wins"]["2018"] ) # first access the wins key, then the next key

Go ahead and run the cell. This will output “108” in the second statement. We’re able to access this information by accessing the first key of “wins” followed by the second key of “2018”.

MONDAY EXERCISES

1. 
   User Input: ask the user for their name and age, and then create a dictionary with those key-value pairs. output the dictionary once created.
   
2.