Fun with hash tables

hash.py

students = [
    ['foo', 'junior'],
    ['bar', 'senior'],
    ['baz', 'junior'],
    ['quux', 'junior'],
    ['guacamole', 'senior'],
    ['spatula', 'junior'],
    ['firewood', 'senior'],
]

ht = {}
for student in students:
    name, level = student
    print(f'Adding {name} to the list of {level}s...')
    if level in ht:
        names = ht[level]
        print(f'Before: {names}')
        names.append(name)
        print(f'After: {names}')
        ht[level] = names
    else:
        print(f'Before: []')
        ht[level] = [name]
        print(f'After: {ht[level]}')
    print()

for level, names in ht.items():
    print(level)
    for name in names:
        print('\t', name)

ht = {}
for student in students:
    name, level = student
    print(f'Incrementing the number of {level}s...')
    if level in ht:
        count = ht[level]
        print(f'Before: {count}')
        count += 1
        print(f'After: {count}')
        ht[level] = count
    else:
        print(f'Before: 0')
        ht[level] = 1
        print(f'After: {ht[level]}')
    print()

import pprint
pprint.pprint(ht)