A vocabulary quiz written for Python 2

questions_and_answers.json

{
"easy" :[
{"question" : "{} is a popular programming language that boasts high-readability code. You might think it was named after a snake species, but it was actually named after a British comedy act.", "answer" : "python"},
{"question" : "The python interpreter can interpret and manipulate various types of data. A whole number is referred to as an {}, while a decimal is known as a float.", "answer" : "integer"},
{"question" : "Another data type is called a {}. It can contain letters, words, sentences, or other characters saved as text.", "answer" : "string"},
{"question" : "Another useful data type in python is a {}, which stores a sequence of values separated by commas.", "answer": "list"}
],

"medium" :[
{"question" : "One of the first steps when learning to code is to learn how to assign a value to a {}, which then stores that value in the computer's memory.", "answer" : "variable"}, 
{"question" : "Next you will probably want to learn how to use simple {}s such as +, -, *, /, >, <, ==, and !=.", "answer" : "operator"},
{"question" : "Once you've mastered variables and operators, it's time to start learning how to write some simple {}s (aka functions), which consist of lines of code that run in a specified order and can eliminate redundancy.", "answer" : "procedure"}, 
{"question" : "A procedure takes one or more {}s as arguments, and returns one or more outputs.", "answer" : "input"}
],

"hard" :[
{"question" : "One important programming construct is called an {} statement; it tests whether a condition is true, and if so it may execute a block of code.", "answer" : "if"},
{"question" : "Another important construct used especially when writing procedures is a {}, which allows you to keep running the same code repeatedly under specified conditions.", "answer" : "loop"}, 
{"question" : "There are two common types of these repeating operations; one is called a {} loop; it runs through all of the values in a specified range.", "answer" : "for"},
{"question" :"The other is called a {} loop; this one runs repeatedly as long as a specified condition is true.", "answer" : "while"}
]
}

Vocab_quiz.py

#!/usr/bin/env python
# This program is a fill-in-the blank quiz, prompting for user input at each blank.

import os
import json

with open('questions_and_answers.json', 'r') as f:
    content = f.read()
    content_dict = json.loads(content)

def evaluate(user_input, correct_answer):
#procedure that evaluates user response
	if user_input.lower() == correct_answer:
		return True
	return False	

def quiz_summary(errors):
#print out a final message at the end of the quiz
        accuracy = '{0:.2f}'.format(4.0/(errors + 4) * 100)
        print "{} {} {}".format("\nCongratulations! You survived the quiz. Your accurracy was", 
                accuracy, "percent.\n")
        last_input = raw_input("How was your experience? ")
        print "{} {} {}".format("\nGlad to hear it was", last_input.lower(), ". See you later!")

def clear_terminal():
        os.system('cls' if os.name == 'nt' else 'clear')


def set_difficulty():
        #difficulty is set through user input
        difficulty = raw_input("\nTo select the difficulty setting, please enter easy, medium, or hard: ")
        while difficulty not in content_dict:
                difficulty = raw_input("Please enter a valid difficulty level: ")
        return difficulty

def run_quiz():
        clear_terminal()

        print "Welcome to the quiz!"

        difficulty = set_difficulty()

        score = 0
        errors = 0

        clear_terminal()

        for i, question_answer in enumerate(content_dict[difficulty]):
                question = question_answer["question"]
                answer = question_answer["answer"]
                print "{0} {1} {2}{2}{3}".format("Question", str(i+1), "\n", question.format("__"+str(i+1)+"__"))

                #appropriate prompt for response printed based on index
                user_input = raw_input("\nType the answer for question " + str(i+1) + ": ")

                if evaluate(user_input, answer):
                        score += 1	        
                        print "\n\n\n\n\nGreat!\n\n" + question.format(answer) + "\n\nYour score is " + str(score)
                        clear_terminal()
                else:
                        errors += 1
                        print "\nNope! Try again."

        quiz_summary(errors)

run_quiz()