Exercise 41 calls for making old fashion flashcards to memorize 10 definitions. I wrote a short script to automate this process (before I realized Zed did the same thing on the next page!). It was a good learning experience as it took me a few hours to figure out how to get the questions to appear randomly without replacement, and I found it quite useful for memorizing the definitions.
Without further adieu, here is flashcards.py
import random
print(’\n’)
“#” create pairs of terms: definitions (key=value)
Obj_Or_Dict = {
‘class’: “Tell Python to make a new type of thing”,
‘object’: “Two meanings - the most basic type of thing, and any instance of some thing”,
‘instance’: “What you get when you tell python to create a class”,
‘def’: “How you define a funcition within a class”,
‘self’: “Inside the functions in a class, ‘?’ is a variable for the instance/object being accessed”,
‘inheritance’: “The concept that one class can inherit traits from another class”,
‘composition’: “The concept that a class can be composed of other classes as parts”,
‘attributes’: “A property classes have that are from composition and are usually variables”,
‘is-a’: “A phrase to say something inherits from another things”,
‘has-a’: “A phrase to say that something is composed of other things or has a trait”
}
Challenge: Can you separate data and functionality in such a way that your script reads the flash cards from a file? Then you’d have a generic flash card trainer that you could use to drill whatever you want.
Tip: Adapt to Python’s internal naming style (only lowercase_with_underscores for function and variable names, CamelCase for class names). And try to find expressive names for things: obj_or_list doesn’t tell much about anything, why not call it cards? — That will make your code easier to read for others.
@florian thanks for the tips, and challenge accepted! Here’s my updated flashcards.py
import random
from sys import argv
script, cards_file = argv
# cards_file is a text file that stores terms and definitions, separated by a colon; one pair of term: definition per line
# example - class: Tell Python to make a new type of thing
print('\n')
flashcards_list = []
with open(cards_file) as f:
# create pairs of [term: definition] and store in flashcards_list
for line in f:
pairs = line.strip().split(':')
flashcards_list.append(pairs)
def flashcards():
while len(flashcards_list) > 0:
#randomly select a pair of term: definition from flashcards_list
answer, question = random.choice(flashcards_list)
print("What is:", question, "?\n")
user_answer = str(input(">>> ")).lower()
if user_answer == answer:
print("\nCorrect!\n")
else:
print("\nIncorrect, dummy. The answer is '{}'\n".format(answer))
flashcards_list.pop(flashcards_list.index([answer, question]))
flashcards()
Curious, where can I find the naming conventions for Python? Perhaps I haven’t read far enough through the book yet.
