| class Calculator: | |
| def __init__(self): | |
| self.expression = "" | |
| self.result = "" | |
| def press(self, key): | |
| if key == "C": | |
| self.expression = "" | |
| self.result = "" | |
| return | |
| if key == "=": | |
| try: | |
| self.result = str(eval(self.expression)) | |
| self.expression = self.result | |
| except: | |
| self.result = "Error" | |
| return | |
| self.expression += key | |
| def get_display(self): | |
| return self.result if self.result else self.expression | |