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Python

Bapi Roy
Bapi Roy
14,237 Points

What is wrong with my implementation of classmethod?

Why am I getting bummer! didnot get the right...

Could anyone please explain to me, what am I doing wrong with classmethod?

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, str):
        return cls(str)


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

1 Answer

Rich Zimmerman
Rich Zimmerman
24,063 Points

So the class is instantiated with a pattern in the form of a list. In this case you want to be able to instantiate it with a string, but the string needs to be converted

"dash-dot"
# needs to convert to
['_', '.']

So all you really need to do is the reverse of your str method by first converting your string to a list, separated by the hyphens

list_pattern = str.split("-")
# will turn it into
['dash', 'dot']

And from there you can loop through, converting the strings to actual dashes and dots and finally returning the new class

return cls(list_pattern)
Bapi Roy
Bapi Roy
14,237 Points

Thank you for your explanation!