Python: Dictionary within dictionary?

Question

I need help with a pretty simple exercise I am trying to execute, just syntactically I'm a bit lost.

Basically I read in a very brief text file containing 15 lines of 3 elements (essentially 2 keys and a value)

• put those elements into a dictionary comprised of dictionaries
• the 1st dictionary contains location and the 2nd dictionary which is made up of the type of the item and how much it costs

For Example:

Location   Item     Cost
------------------------
gymnasium  weights  15 

market     cereal   5

gymnasium  shoes    50

saloon     beer     3

saloon     whiskey  10

market     bread    5

Which would result in

{'gymnasium': {'weights': 15, 'shoes': 50}

and so on for the other keys

Basically I need to loop through this file but I'm struggling to read in the contents as a dict of dicts. Moreover without that portion i can't figure out how to append the inner list to the outer list if an instance of the key in the outer list occurs.

Answer 1

This looks like homework, so I'll only provide a few hints.

You probably know that this is how you create a new dictionary:

d = {}

Adding an entry to a dictionary:

d[key] = value

More specifically, adding an entry whose key is a string and whose value is another dictionary:

d["gymnasium"] = {}

Now, whenever you write d["gymnasium"] as a part of a larger expression, you'll get access to that inner dictionary, and you can perform the usual dictionary operations on it, e.g. using [] and = to add something to it:

d["gymnasium"]["weights"] = 15