change the name of the lb button to lb(kg) and the name of the kg button to kg(lb) but do not change waht the copy in the execution filed: lb() and kg(). Print only the parts that need to be changed. Think step by step. Python code: import ctypes
import math
import re
from typing import Any, Dict, Union

import tkinter as tk
from tkinter import font as tkFont, ttk

# Revised Function for Capitalization
def capitalize_sentence(sentence: str) -> str:
    """Capitalize the first letter of each word in the sentence."""
    return ' '.join(word[0].upper() + word[1:].lower() for word in sentence.split())

# Conversion Functions
def kg_to_lb(kg: float) -> float:
    """Convert kilograms to pounds."""
    return kg / 0.45359237

def lb_to_kg(lb: float) -> float:
    """Convert pounds to kilograms."""
    return lb * 0.45359237

# Evaluation Function
def evaluate_expression(expression: str, use_degrees: bool = False) -> Union[float, str]:
    """Safely evaluate a mathematical expression considering degree mode."""

    def convert_angle(func: Any, x: float) -> float:
        return func(math.radians(x)) if use_degrees else func(x)

    def inverse_convert_angle(func: Any, x: float) -> float:
        result = func(x)
        return math.degrees(result) if use_degrees else result

    safe_functions: Dict[str, Any] = {
        "sqrt": math.sqrt,
        "sin": lambda x: convert_angle(math.sin, x),
        "cos": lambda x: convert_angle(math.cos, x),
        "tan": lambda x: convert_angle(math.tan, x),
        "asin": lambda x: inverse_convert_angle(math.asin, x),
        "acos": lambda x: inverse_convert_angle(math.acos, x),
        "atan": lambda x: inverse_convert_angle(math.atan, x),
        "log": math.log10,
        "ln": math.log,
        "pi": math.pi,
        "e": math.e,
        "lb": kg_to_lb,
        "kg": lb_to_kg,
        "capitalize": capitalize_sentence  # Updated to handle entire sentences
    }

    expression = expression.replace("^", "**")
    expression = re.sub(r'\bcapitalize\((\w+)\)', r'capitalize("\1")', expression)

    func_calls = re.findall(r"(\b\w+\b)\(([^)]+)\)", expression)

    for func, arg in func_calls:
        if func in ["asin", "acos"]:
            try:
                value = eval(arg, {"__builtins__": None}, safe_functions)
                if not -1 <= value <= 1:
                    raise ValueError(f"{func}(x) is undefined for |x| > 1")
            except Exception as e:
                return f"Error: {e}"

    try:
        result = eval(expression, {"__builtins__": None}, safe_functions)
        if isinstance(result, float) and abs(result) < 1e-10:
            result = 0.0
        return round(result, 2) if isinstance(result, (int, float)) else result
    except Exception as e:
        return f"Error: {e}"

# Calculator GUI Class
class CalculatorGUI:
    """Tkinter-based Calculator with Degrees/Radians toggle and history."""

    def __init__(self, master: tk.Tk) -> None:
        self.master = master
        self.use_degrees: tk.BooleanVar = tk.BooleanVar(value=False)
        self.set_dpi_awareness()
        self.setup_window()
        self.create_widgets()
        self.layout_widgets()
        self.configure_grid()

    def set_dpi_awareness(self) -> None:
        """Enable high-DPI support on Windows."""
        try:
            ctypes.windll.shcore.SetProcessDpiAwareness(1)
        except Exception:
            pass

    def setup_window(self) -> None:
        """Configure the main application window."""
        self.master.title("Calculator")
        self.master.geometry("1200x720")

    def create_widgets(self) -> None:
        """Initialize all GUI components."""
        self.font: tkFont.Font = tkFont.Font(family="Roboto Flex", size=16)
        self.button_font: tkFont.Font = tkFont.Font(family="Roboto Flex", size=14)
        self.expression_var: tk.StringVar = tk.StringVar()
        self.entry: ttk.Entry = ttk.Entry(
            self.master, textvariable=self.expression_var, font=self.font, width=50
        )
        self.entry.bind("<Return>", self.calculate)

        self.history_text: tk.Text = tk.Text(
            self.master,
            width=70,
            height=10,
            font=self.font,
            wrap="none",
            state=tk.DISABLED,
        )

        self.scrollbar: ttk.Scrollbar = ttk.Scrollbar(
            self.master, orient="vertical", command=self.history_text.yview
        )
        self.history_text.configure(yscrollcommand=self.scrollbar.set)

        # Create buttons for functions
        self.function_buttons = {
            "Functions": ["sqrt", "sin", "cos", "tan", "asin", "acos", "atan", "log", "ln"],
            "Conversions": ["lb", "kg"],
            "Unique": ["capitalize"],
            "Constants": ["pi", "e"]
        }
        self.function_frame = ttk.Frame(self.master)
        self.create_function_buttons()

    def create_function_buttons(self):
        """Create buttons for inserting functions into the entry."""
        # Functions category with three columns
        ttk.Label(self.function_frame, text="Functions", font=self.button_font).grid(
            row=0, column=0, columnspan=3, padx=5, pady=5, sticky="n"
        )
        funcs = self.function_buttons["Functions"]
        for i, func in enumerate(funcs):
            button = ttk.Button(
                self.function_frame,
                text=func,
                command=lambda f=func: self.insert_function(f),
                width=10,
                style='Function.TButton'
            )
            button.grid(row=(i // 3) + 1, column=(i % 3), padx=5, pady=5)

        # Other categories with one column each
        col = 0
        for category in ["Conversions", "Unique", "Constants"]:
            col += 3
            ttk.Label(self.function_frame, text=category, font=self.button_font).grid(
                row=0, column=col, padx=5, pady=5, sticky="n"
            )
            funcs = self.function_buttons[category]
            for i, func in enumerate(funcs):
                button = ttk.Button(
                    self.function_frame,
                    text=func,
                    command=lambda f=func: self.insert_function(f),
                    width=10,
                    style='Function.TButton'
                )
                button.grid(row=i + 1, column=col, padx=5, pady=5)

        # Add the Settings category with the Radians/Degrees button
        col += 1
        ttk.Label(self.function_frame, text="Settings", font=self.button_font).grid(
            row=0, column=col, padx=5, pady=5, sticky="n"
        )
        self.create_toggle_button(col)

    def insert_function(self, function: str) -> None:
        """Insert function text into the expression entry."""
        current_text = self.expression_var.get()
        new_text = f"{current_text}{function}()"
        self.expression_var.set(new_text)
        self.entry.icursor(len(new_text) - 1)  # Move the cursor inside the parentheses

    def create_toggle_button(self, col: int) -> None:
        """Create the Degrees/Radians toggle button in the settings column."""
        style: ttk.Style = ttk.Style()
        style.configure("ToggleButton.TButton", font=self.button_font, padding=0)
        style.configure('Function.TButton', font=self.button_font)  # Set style for function buttons
        self.mode_button: ttk.Button = ttk.Button(
            self.function_frame,
            text="Radians",
            command=self.toggle_mode,
            style="ToggleButton.TButton",
            width=10
        )
        self.mode_button.grid(row=1, column=col, padx=5, pady=5)

    def layout_widgets(self) -> None:
        """Arrange widgets within the window."""
        self.entry.grid(row=0, column=0, columnspan=5, padx=5, pady=5, sticky="ew")
        self.history_text.grid(row=1, column=0, columnspan=4, padx=5, pady=5, sticky="nsew")
        self.scrollbar.grid(row=1, column=4, padx=(0, 5), pady=5, sticky="ns")
        self.function_frame.grid(row=2, column=0, columnspan=5, padx=5, pady=5, sticky="ew")

    def configure_grid(self) -> None:
        """Make the grid layout responsive."""
        self.master.columnconfigure(0, weight=1)
        self.master.columnconfigure(1, weight=0)
        self.master.rowconfigure(1, weight=1)

    def toggle_mode(self) -> None:
        """Switch between Degrees and Radians modes."""
        if self.use_degrees.get():
            self.use_degrees.set(False)
            self.mode_button.config(text="Radians")
        else:
            self.use_degrees.set(True)
            self.mode_button.config(text="Degrees")

    def calculate(self, event: tk.Event = None) -> None:
        """Evaluate the expression and update history."""
        expression: str = self.expression_var.get().strip()
        if not expression:
            return
        result: Union[float, str] = evaluate_expression(
            expression, use_degrees=self.use_degrees.get()
        )
        self.display_result(expression, result)
        self.expression_var.set("")

    def display_result(self, expression: str, result: Union[float, str]) -> None:
        """Append the calculation to the history log."""
        self.history_text.config(state=tk.NORMAL)
        mode: str = "Degrees" if self.use_degrees.get() else "Radians"
        self.history_text.insert(tk.END, f"[{mode}] {expression} = {result}\n")
        self.history_text.config(state=tk.DISABLED)
        self.history_text.see(tk.END)

# Main Function
def main() -> None:
    """Run the Calculator application."""
    root: tk.Tk = tk.Tk()
    CalculatorGUI(root)
    root.mainloop()

if __name__ == "__main__":
    main()