用python写简单的计算器，具有图形用户界面，能实现常用的算术计算功能。 【功能需求】 （1）具有图形用户界面。 （2）能实现加、减、乘、除基本运算和清零功能。 （3）计算器每次启动时按键的位置随机变换。 （4）计算器至少有“查看”、“帮助”两个菜单，可扩展计算器的其他功能

好的，我可以为您提供一个简单的Python计算器，具有图形用户界面，并能实现加、减、乘、除和清零功能。以下是代码：

from tkinter import *

class Calculator:
    def __init__(self, master):
        self.master = master
        master.title("简单计算器")
        master.geometry("250x200")

        # 创建显示框
        self.display = Entry(master, width=25, font=('Arial', 14))
        self.display.grid(row=0, column=0, columnspan=4, pady=5)

        # 创建按钮
        self.button_1 = Button(master, text="1", command=lambda: self.button_click(1))
        self.button_2 = Button(master, text="2", command=lambda: self.button_click(2))
        self.button_3 = Button(master, text="3", command=lambda: self.button_click(3))
        self.button_4 = Button(master, text="4", command=lambda: self.button_click(4))
        self.button_5 = Button(master, text="5", command=lambda: self.button_click(5))
        self.button_6 = Button(master, text="6", command=lambda: self.button_click(6))
        self.button_7 = Button(master, text="7", command=lambda: self.button_click(7))
        self.button_8 = Button(master, text="8", command=lambda: self.button_click(8))
        self.button_9 = Button(master, text="9", command=lambda: self.button_click(9))
        self.button_0 = Button(master, text="0", command=lambda: self.button_click(0))
        self.button_clear = Button(master, text="清零", command=self.button_clear)
        self.button_add = Button(master, text="+", command=lambda: self.button_operation('+'))
        self.button_subtract = Button(master, text="-", command=lambda: self.button_operation('-'))
        self.button_multiply = Button(master, text="×", command=lambda: self.button_operation('×'))
        self.button_divide = Button(master, text="÷", command=lambda: self.button_operation('÷'))
        self.button_equal = Button(master, text="=", command=self.button_equal)

        # 随机排列按钮
        self.buttons = [self.button_1, self.button_2, self.button_3, self.button_4, 
                        self.button_5, self.button_6, self.button_7, self.button_8, 
                        self.button_9, self.button_0, self.button_clear, self.button_add, 
                        self.button_subtract, self.button_multiply, self.button_divide, self.button_equal]
        random.shuffle(self.buttons)

        # 将按钮放置在界面上
        row = 1
        col = 0
        for button in self.buttons:
            button.grid(row=row, column=col, pady=5)
            col += 1
            if col > 3:
                col = 0
                row += 1

        # 创建菜单
        self.menu = Menu(master)
        master.config(menu=self.menu)
        self.view_menu = Menu(self.menu)
        self.menu.add_cascade(label="查看", menu=self.view_menu)
        self.view_menu.add_command(label="显示历史记录")
        self.help_menu = Menu(self.menu)
        self.menu.add_cascade(label="帮助", menu=self.help_menu)
        self.help_menu.add_command(label="关于计算器")

        # 创建历史记录窗口
        self.history_window = Toplevel(master)
        self.history_window.title("历史记录")
        self.history_window.geometry("250x200")
        self.history_window.withdraw()

    def button_click(self, number):
        current = self.display.get()
        self.display.delete(0, END)
        self.display.insert(0, str(current) + str(number))

    def button_clear(self):
        self.display.delete(0, END)

    def button_operation(self, operator):
        self.first_number = float(self.display.get())
        self.operator = operator
        self.display.delete(0, END)

    def button_equal(self):
        second_number = float(self.display.get())
        if self.operator == '+':
            result = self.first_number + second_number
        elif self.operator == '-':
            result = self.first_number - second_number
        elif self.operator == '×':
            result = self.first_number * second_number
        elif self.operator == '÷':
            result = self.first_number / second_number
        self.display.delete(0, END)
        self.display.insert(0, result)

    def show_history(self):
        self.history_window.deiconify()

root = Tk()
calculator = Calculator(root)
root.mainloop()

此外，为了实现计算器每次启动时按键位置的随机变换，我们可以使用 `random.shuffle()` 函数来随机排列按钮的顺序。