44 lines
1.0 KiB
Python
44 lines
1.0 KiB
Python
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import abc
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class State(object, metaclass=abc.ABCMeta):
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def __init__(self):
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self.color_index = 0
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@abc.abstractmethod
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def light(self):
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COLORS = ["Green", "Red", "Blue", "Yellow"]
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state_color = COLORS[self.color_index]
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self.color_index += 1
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if self.color_index == len(COLORS):
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self.color_index = 0
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return state_color
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class Lamp(State):
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def __init__(self):
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super().__init__()
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self.color = None
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def light(self):
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self.color = super().light()
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return self.color
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if __name__ == '__main__':
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# These "asserts" using only for self-checking and not necessary for auto-testing
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lamp_1 = Lamp()
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lamp_2 = Lamp()
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lamp_1.light() # Green
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lamp_1.light() # Red
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lamp_2.light() # Green
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assert lamp_1.light() == "Blue"
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assert lamp_1.light() == "Yellow"
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assert lamp_1.light() == "Green"
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assert lamp_2.light() == "Red"
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assert lamp_2.light() == "Blue"
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print("Coding complete? Let's try tests!")
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