Hangman (based of TIY assignment)

hangman.py

import random
from string import ascii_uppercase

def get_difficulty():

    difficulty_length = {'easy': (4, 6),
                         'medium': (6, 8),
                         'hard': (8, 20)
                         }

    difficulty_request = input("What's your selected difficulty? EASY, MEDIUM, HARD ? \n> ").lower()

    while difficulty_request not in ['easy', 'medium', 'hard']:
        difficulty_request = input(
            "Please input EASY, MEDIUM, or HARD.\n> ").lower()

    return difficulty_length[difficulty_request]


def load_word(min_length, max_length):
    capitals = list(ascii_uppercase)
    with open('/usr/share/dict/words', 'r') as f:
        words = [i.strip() for i in f.readlines() if len(i.strip()) < max_length and len(i.strip()) > min_length and i[0] not in capitals]
    selection = random.choice(words)
    return selection

def display_word(word, filled_characters=[]):
    blank = list("_" * len(word))
    if filled_characters is None:
        display = ' '.join(blank)
        return display
    word_characters = list()
    for filled_character in filled_characters:
        for i, character in enumerate(word):
            if character == filled_character:
                blank[i] = filled_character.upper()

    display = ' '.join(blank)

    return display

def check_guess(word):
    character_guess = input("Please guess a character: \n> ")
    if character_guess in word:
        return character_guess
    else:
        return None


def main():
    guess_history = []
    attempts = 8
    difficulty = get_difficulty()
    selected_word = load_word(difficulty[0], difficulty[1])
    win_condition = False

    print("HINT:", selected_word)

    print("Your current status:")
    print(display_word(selected_word))

    while attempts != 0 and win_condition == False:
        guess = check_guess(selected_word)

        if guess:
            if guess in guess_history:
                print("You've already guessed that. Try again")
                guess = check_guess(selected_word)
            else:
                print("You've guessed correct!")
                guess_history.append(guess)
                if display_word(selected_word, guess_history).find("_") == -1:
                    print("YOU'VE WON!")
                    print(display_word(selected_word, guess_history))
                    win_condition = True
                    exit()
                else:
                    print(display_word(selected_word, guess_history))
                    attempts -= 1
        else:
            print("Sorry, your character isn't in the word.")
            print("Current Status:")
            print(display_word(selected_word, guess_history))
            attempts -= 1

    print("Out of Attempts, Try again!")
    exit()

if __name__ == "__main__":
    main()