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Python

Posted by isaacrichardson
isaacrichardson
14,313 Points

Let's use __str__ to turn Python code into Morse code! OK, not really, but we can turn class instances into a representa

Let's use str to turn Python code into Morse code! OK, not really, but we can turn class instances into a representation of their Morse code counterparts. I want you to add a str method to the Letter class that loops through the pattern attribute of an instance and returns "dot" for every "." (period) and "dash" for every "" (underscore). Join them with a hyphen. I've included an S class as an example (I'll generate the others when I test your code) and it's __str_ output should be "dot-dot-dot".

The code is working, what's wrong with it

morse.py 
class Letter:
    def __init__(self, pattern=None):
        self.pattern = pattern

    def __str__(self):
        morse = []
        for i in self.pattern:
            if i == '.':
                morse.append("dot")
            if i == "_":
                morse.append("dash")

        return "-".join(morse)


class S(Letter):
    def __init__(self):
        pattern = ['.', '.', '.']
        super().__init__(pattern)

12 Answers

Jeff Muday
MOD
Jeff Muday
Treehouse Moderator 28,720 Points
Jeff Muday
Jeff Muday
Treehouse Moderator 28,720 Points

I pasted in just the str() method you wrote and worked perfectly. Nice job!

I would try re-doing the challenge. It's hard to say where miscommunication between browser, editor, and server goes wrong without examining the logs (which I don't have access to). It can sometimes be as trivial as substitution of space and tab characters or unexpected "kerning" of fonts where indents visually look fine, but Python rules differently.

I feel confident that it should work if other challenges were working for you before.

    def __str__(self):
            morse = []
            for i in self.pattern:
                if i == '.':
                    morse.append("dot")
                if i == "_":
                    morse.append("dash")

            return "-".join(morse)
Leonard Foster
Leonard Foster
14,806 Points
Leonard Foster
Leonard Foster
14,806 Points

I feel lost in this course, anyone else feel it could be a little more clear?

Anthony Parker
Anthony Parker
1,454 Points
Anthony Parker
Anthony Parker
1,454 Points

Yes, very unclear on the learning objective.

Mitchell Beck
Mitchell Beck
5,836 Points
Mitchell Beck
Mitchell Beck
5,836 Points

Generally, Treehouse courses are great, this is the first one that I am having trouble understanding!

Roger Perez
Roger Perez
8,676 Points

OMG I feel a little better that i'm not the only one that feels that way. I felt like my learning was going great until I got to OOP and it thru me off bad. I'm very curious, how are you all feeling about it now that some time has passed? Do you feel like you have a better understanding. I have been loving learning python so far but this threw me off so much that I feel a drop in motivation. Pushing through it tho! Really looking forward to hearing how you guys feel on it now.

RWS Admin
RWS Admin
19,205 Points
RWS Admin
RWS Admin
19,205 Points

I am with you all. I am really struggling with this course. I've been watching some youtube tutorials on python and that's been helping a bit. Hopefully they redo this course with one of the newer instructors.

Zachary Ponder
Zachary Ponder
6,704 Points
Zachary Ponder
Zachary Ponder
6,704 Points

I feel like I NEVER want to take another one of Kenneth Love's courses.

Laurens Salcedo Valdez
Laurens Salcedo Valdez
3,117 Points
Laurens Salcedo Valdez
Laurens Salcedo Valdez
3,117 Points

Felt the same way for some time, I suggest for anyone else having this issue to tackle the subject in a different way. Try to divide the subject in different blocks, look at the teacher's note and try to understand why certain challenges are resolved in a certain way. It took me some time to get a hang of it, but as Kenneth said it is a tricky subject.

Don't lose hope! Once you get through this you will feel so much better and you will be able to continue your journey of learning Python.

Aliaksandr Khvastovich
Aliaksandr Khvastovich
7,864 Points

yep, it is like how did I get here from functions...

Flamie Mushawatu
Flamie Mushawatu
4,135 Points

Hey guys i know this is really old now , but if anyone found an easier way to understand this ,i would really appreciate a hand...😓

Yoon Choi
Yoon Choi
1,649 Points
Yoon Choi
Yoon Choi
1,649 Points

I agree, it so confusing. We wish someone else can re-teach the OOP. PLEASE!

Titose Chembezi
Titose Chembezi
3,361 Points
Titose Chembezi
Titose Chembezi
3,361 Points

I think OO module should be redone. I was fine with the previous modules

Jeff Muday
MOD
Jeff Muday
Treehouse Moderator 28,720 Points
Jeff Muday
Jeff Muday
Treehouse Moderator 28,720 Points

The string method "join()" does a joining of list items and separating each with the string supplied and returns a string. This is a little tricky at first if you are coming from a JavaScript or Ruby background where join() works differently.

Here's a simple Python example using mylist and mystring.

mylist = ['How','are','you']
mystring = "$".join(mylist)

After running the code, the variable "mystring" will contain "How$are$you".

Notice that the dollar-sign character is imposed in between each list element of mylist.

In the context of the code challenge

morse_list = ['dot','dash','dot']
morse_string = "-".join(morse_list)

After the code is run, the variable morse_string will contain "dot-dash-dot"

Michal Bednář
Michal Bednář
3,116 Points
Michal Bednář
Michal Bednář
3,116 Points

This OOP module is terrible. Please remake it with somebody else. All the courses in this track with previous two teachers were amazing but this is just terrible.

devin leyba
devin leyba
7,209 Points
devin leyba
devin leyba
7,209 Points

I agree, needs to be explained better

Arturas Budreika
seal-mask
.a{fill-rule:evenodd;}techdegree
Arturas Budreika
Python Development Techdegree Student 5,464 Points
Arturas Budreika
.a{fill-rule:evenodd;}techdegree
Arturas Budreika
Python Development Techdegree Student 5,464 Points

This is so bad... I am watching material over and over and still do not get it...

Cheo R
Cheo R
37,150 Points
Cheo R
Cheo R
37,150 Points

You might have a spacing issue, I copied and pasted your exact code and it passed.

anthony pizarro
anthony pizarro
1,983 Points
anthony pizarro
anthony pizarro
1,983 Points

what does the '-'.join(morse) do?

Leonard Foster
Leonard Foster
14,806 Points

@anthony pizarro: joins a list of strings together with a "-" between. ie ["dot", "dot", "dot"] becomes "dot-dot-dot"

drew s
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
drew s
Python Development Techdegree Graduate 19,491 Points
drew s
.a{fill-rule:evenodd;}techdegree seal-36
drew s
Python Development Techdegree Graduate 19,491 Points

I agree with all of you.. I was enjoying each course in techdegree for Python and when I reached OOP course I started to lose interest. I thought I was the only one who's struggling in the course.

noel acio
noel acio
1,470 Points
noel acio
noel acio
1,470 Points

glad to read your comments and how you guys feel about OO,.