Codehunter-py

Classes and Methods Cheat Sheet (Optional)
Classes and Methods Cheat Sheet
In the past few videos, we’ve seen how to define classes and methods in Python. Here, you’ll find a run-down of everything we’ve covered, so you can refer to it whenever you need a refresher.

Defining classes and methods
############################################
class ClassName:
    def method_name(self, other_parameters):
        body_of_method
Classes and Instances

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def counter(start, stop):
    x = start
    if x > stop:
        return_string = "Counting down: "
        while x >= stop:
            return_string += str(x)+","
            x -= 1
    else:
        return_string = "Counting up: "
        while x < stop:

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def add_prices(basket):
	
	total = 0
	for price in basket.values():
		total += price
	
	return round(total, 2)  

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def groups_per_user(group_dictionary):
    user_groups = {}
    for group, users in group_dictionary.items():
        for user in users:
            if user not in user_groups:
                user_groups[user] = []
            user_groups[user].append(group)
    return user_groups

print(groups_per_user({"local": ["admin", "userA"],

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def email_list(domains):
    emails = []
    for domain, users in domains.items():
          for user in users:
              emails.append(user+'@'+domain)
    return(emails)

print(email_list({"gmail.com": ["clark.kent", "diana.prince", "peter.parker"], \
"yahoo.com": ["barbara.gordon", "jean.grey"], "hotmail.com": ["bruce.wayne"]}))

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Definition

x = {key1:value1, key2:value2} 

Operations

len(dictionary) - Returns the number of items in the dictionary

for key in dictionary - Iterates over each key in the dictionary

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def count_letters(text):
    result = {}
    for char in text:
        if char not in result:
            result[char] = 0
        result[char] += 1
    return result
    

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def guest_list(guests):
	for guest in guests:
		name, age, job = guest
		print("{} is {} years old and works as {}".format(name, age, job))

guest_list([('Ken', 30, "Chef"), ("Pat", 35, 'Lawyer'), ('Amanda', 25, "Engineer")])

#Click Run to submit code
"""
Output should match:

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filenames = ["program.c", "stdio.hpp", "sample.hpp", "a.out", "math.hpp", "hpp.out"]
# Generate newfilenames as a list containing the new filenames
# using as many lines of code as your chosen method requires.
newfilenames = [x.replace('.hpp','.h') for x in filenames]

print(newfilenames) 
# Should be ["program.c", "stdio.h", "sample.h", "a.out", "math.h", "hpp.out"]

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def pig_latin(text):
  words = text.split()
  pigged_text = []

  for word in words:
    word = word[1:] + word[0] + 'ay'
    pigged_text.append(word)

  return ' '.join(pigged_text)