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Python

Hi, I really need help on this challenge

Maybe i am not understanding what the question is asking! Let's practice using @classmethod!

Create a class method in Letter named from_string that takes a string like "dash-dot" and creates an instance with the correct pattern (['_', '.']). What exacly am i suppose to do here?

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

    def __iter__(self):
        yield from self.pattern

    def __str__(self):
        output = []
        for blip in self:
            if blip == '.':
                output.append('dot')
            else:
                output.append('dash')
        return '-'.join(output)

    @classmethod
    def from_string(cls, my_string):
        pattern = my_string.split("-")
        for element in pattern:
            if element == "dash":
                pattern.remove("dash")
                pattern.append("_")
            else:
                pattern.remove("dot")
                pattern.append(".")
        return cls(pattern)

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

2 Answers

Ryan Gostic
Ryan Gostic
20,790 Points

Mutating (Changing) a list while iterating through it is not a good practice. Try creating a new list to add the new '.' and '-'.

i really want you to focus in this

class S(Letter): def init(self): pattern = ['.', '.', '.'] # make sure you put the pattern value in its place super().init(pattern=pattern)