Dictionary Help

Software Development Programming Help
#1

I am currently going through the book “Python Crash course” by Eric Matthes, and I am having a really hard time understanding some of the code. I am teaching myself just because I think coding could be a really fun hobby. So here is what I am struggling with.

Chapter 6 Dictionaries and If you own the book it is favorite_languages.py on pg 102.

favorite_languages = {
‘jen’ : ‘python’,
'sarah : ‘c’,
‘edward’ : ‘ruby’,
‘phil’ : ‘python’,
}
friends = [‘phil’, ‘sarah’]
for name in favorite_languages.keys():
print(f"Hi {name.title()}.")

if name in friends:
       language = favorite_languages[name].title()
       print(f"\t{name.title()}, I see you love {language}!")

We get the output

Hi Jen.
Hi Sarah.
Sarah, I see you love C!
Hi Edward.
Hi Phil.
Phil, I see you love Python!

I understand what they are trying to do, but my brain does not understand the coorelations, and why we are getting that output. So i was hoping someone could break this down for me and explain exactly whats going on.

Thanks

#2

Hey @Lundo1 and welcome to the GitHub Community Forum! Yes, coding could definitely be a fun hobby and everyone can learn! Let me break down the code step-by-step for you.

# Below here, a dictionary is defined. Just like in real life, a
# dictionary in Python maps so-called "keys" (in real-life the words,
# but in this case some names) to "values" (in real-life the
# definitions, but in this case their favorite programming language).
favorite_languages = {
    'jen' : 'python',
    'sarah' : 'c',
    'edward' : 'ruby',
    'phil' : 'python’'
}

# Here, we create a list that contains names of your friends:
friends = ['phil', 'sarah']

# Here we make a for-loop. We loop through the keys, since the keys()
# method of a dictionary returns a list of the keys. In this case:
# favorite_languages.keys() = ['jen', 'sarah', 'edward', 'phil'].
# Similarly, you could also use .values() for the items, or .items()
# for both the key and the value, like:
# > for name, fav_language in favorite_languages.items():
# >     ...
for name in favorite_languages.keys():

    # Using an f-string we print the name. See what is going
    # on in an f-string?
    print(f'Hi {name.title()}.')

    if name in friends:  # If the current name is in the friends list

        # Determine their favorite language. Using square
        # brackets ( [ and ] ) you can access values from a
        # dictionary. In your case: favorite_languages['phil'] == 'python'.
        # The .title() may be a bit confusing, but that method just capitalizes
        # the first letter of the programming language. Leave it out and test
        # what happens!
        language = favorite_languages[name].title()

        # Again, print some info using an f-string.
        print(f'\t{name.title()}, I see you love {language}!')

Hope it helps! If you have any further questions, let us know!

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#3

Thanks for the reply. Sorry I didn’t get back to you sooner, work has been crazy. Really appreciate your help!

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