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Boolean Composites

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Step 2 - Boolean Composites: And / Or

Non-terminal expressions combine other expressions. Each holds child expressions and delegates to them inside interpret.

Implement:

  • And(a, b).interpret(context) returns a.interpret(context) and b.interpret(context).
  • Or(a, b).interpret(context) returns a.interpret(context) or b.interpret(context).

Because children are themselves expressions, you can nest And, Or, Var and Const to any depth.

Hints
Starter code
class Var:
    def __init__(self, name):
        self.name = name

    def interpret(self, context):
        return bool(context.get(self.name, False))


class Const:
    def __init__(self, value):
        self.value = value

    def interpret(self, context):
        return self.value


class And:
    def __init__(self, a, b):
        self.a = a
        self.b = b

    def interpret(self, context):
        """Return the logical AND of the two child results."""
        # TODO: return self.a.interpret(context) and self.b.interpret(context)
        pass


class Or:
    def __init__(self, a, b):
        self.a = a
        self.b = b

    def interpret(self, context):
        """Return the logical OR of the two child results."""
        # TODO: return self.a.interpret(context) or self.b.interpret(context)
        pass
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