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Dmitriy Ignatiev
Dmitriy Ignatiev
Courses Plus Student 6,236 Points


confusing why it prints the same string but not convert to morse as it must. Could you please help me to understand?

test = Letter.from_string('dash-dot') print(test)

dash-dot instead of ['_', '.']

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 == '.':
        return '-'.join(output)

    def from_string(cls, string):
        output2 = []
        x = string.split ('-')
        for i in x:
            if i == 'dash':
                output2.append ('_')
            elif i == 'dot':
                output2.append ('.')
        return cls(output2)

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

1 Answer

Kenneth Love
Kenneth Love
Treehouse Guest Teacher

When you do Letter.from_string(), it turns the pattern you send in, like "dash-dot", into a Morse code pattern, like _ . (of course we're storing it as a list, so ['_', '.']). When you print() a Letter, though, the __str__ method turns the list of dashes and dots into a string like "dash-dot". The from_string() and __str__() methods basically do the opposite of each other.