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Python

Morse code printer: __str__ method

The task is to write a str method in de Letter class that loops over the pattern of S and returns a string where every '.' from the pattern is replaced by the string 'dot' and every '_' by 'dash'. All items from the pattern list 'dot' and 'dash' are joined by a hyphen.

I have tried looping by index, giving the pattern as argument in the dunder str method, working with list.original.copy()-syntax for the looping part but nothing worked. A hint button or code checker would come in very handy, I have no clue of where my mistake is.

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

    def __str__(self):
        a = []
        from c in self.pattern:
            if c == ".":
                a.append("dot")
            elif c == "_":
                a.append("dash")
        return "-".join(a) 

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

1 Answer

Steven Parker
Steven Parker
231,269 Points

You're very close, but the keyword to create a loop is "for" instead of "from".