Build Stream WrappersStep 4 of 5

Repeat with parameters

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Step 4: Repeat with parameters

Decorators can carry their own configuration. A GzipStream might take a compression level; here Repeat takes a times count. Because it needs extra state beyond the wrapped object, it defines its own init that calls the base constructor (to store wrapped) and then saves times.

The init is already written for you. Implement Repeat.read so it returns the wrapped text repeated self.times times. It still stacks with everything else, since it exposes the same read() interface.

Hints
Starter code
class Source:
    def __init__(self, text):
        self.text = text

    def read(self):
        return self.text


class Decorator:
    def __init__(self, wrapped):
        self.wrapped = wrapped

    def read(self):
        return self.wrapped.read()


class UpperCase(Decorator):
    def read(self):
        return self.wrapped.read().upper()


class Reverse(Decorator):
    def read(self):
        return self.wrapped.read()[::-1]


class Repeat(Decorator):
    def __init__(self, wrapped, times):
        super().__init__(wrapped)
        self.times = times

    def read(self):
        """Return the wrapped text repeated self.times times."""
        # TODO:
        #   return self.wrapped.read() * self.times
        pass
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