Nested function code is unreachable - python tkinter

The function firespit can't access any of the code inside of it saying it is unreachable. All the variable inside firespit are also unbound even though I have defined them previously. What i am trying to do is subtract damage of firespit from the health of the opponent. if there is a better way please tell me.

#Set up imports
import tkinter as tk
from tkinter import *
from tkinter.filedialog import *
from tkinter.constants import BOTTOM, LEFT, RIGHT, TOP
import random
from PIL import ImageTk, Image
from tkinter import ttk

#Set up Pokemon
pokemonList = ["Water Turte", "Plot Armour Rat", "Fire Lizard", "Plant with Legs"]

#Pokemon Move lists
fireLizardMoves = {"Firespit":25, "wingbash":15, "bite":20, "flamethrower":1}
plantWithLegsMoves = {"sit":5, "treebash":20, "stomp":25, "naturepower":10}
waterTurtleMoves = {"Water bazuka":25, "sprinkler":20, "SWIM":15,"TurtlePower":3}
plotArmourRatMoves = {"Lightning Bolt":10, "Broken Cpu":25, "SparkyRat":15, "speedyhit":1}

#Pokemon HP
PlayerHp = 0
CompHp = 0
fireLizardHP = 100
PlantWIthLegsHP = 125
WaterTurtleHP = 75
PlotArmourRatHp = 60 

#Set Up Gui
menu = tk.Tk()
menu.title("Pokemon Game")
menu.rowconfigure(0, minsize=800, weight=1)
menu.columnconfigure(1, minsize=800, weight=1)
menu.configure(background= 'black')

#Import Image
imgFirelizard = ImageTk.PhotoImage(Image.open("General/FireLizard.PNG"))
imgPlotArmourRat = ImageTk.PhotoImage(Image.open("General/PlotArmourRat.PNG"))
imgPlantWithLegs = ImageTk.PhotoImage(Image.open("General/PlantWithLegs.PNG"))
imgWaterTurtle = ImageTk.PhotoImage(Image.open("General/WaterTurtle.PNG"))
img=[imgFirelizard,imgPlantWithLegs,imgPlotArmourRat,imgWaterTurtle]

#Set up windows
window1 = tk.Toplevel()
window1.withdraw()
window2 = tk.Toplevel()
window2.withdraw()
window3 = tk.Toplevel()
window3.withdraw()

#Different tabs
def choose_your_character():
    for items in pokemonList:
        window1.title("Choose Your Character")
        window1.rowconfigure(0, minsize=800, weight=1)
        window1.columnconfigure(1, minsize=800, weight=1)
        window1.configure(background= 'black')
        frame = Frame(window1, width=150, height=100)
        frame.place(anchor='center', relx=0.5, rely=0.5)
        label1 = Label(frame, image = imgFirelizard)
        label2 = Label(frame, image = imgPlantWithLegs)
        label3 = Label(frame, image = imgWaterTurtle)
        label4 = Label(frame, image = imgPlotArmourRat)
        label1.pack()
        label2.pack()
        label3.pack()
        label4.pack()
        menu.withdraw()
        window1.deiconify()

def battle_start_fire_Lizard():
    global updatedCompHp
    window2.rowconfigure(0, minsize=800, weight=1)
    window2.columnconfigure(1, minsize=800, weight=1)
    window1.withdraw()
    window2.deiconify()
    window2.configure(background= 'black')
    
    frame1 = Frame(window2, width=2, height=1)
    frame1.place(anchor='w', relx=0.2, rely=0.7)
    label5 = Label(frame1, image = imgFirelizard)
    label5.pack()

    frame2 = Frame(window2, width=2, height=1)
    frame2.place(anchor='w', relx=0.7, rely=0.2)
    
    PlayerHp = fireLizardHP
    CompPokemon = random.choice(img)

    #Set opposing pokemone health, moves, and character
    if CompPokemon == imgFirelizard:
        CompPokemonAttacks = fireLizardMoves
        updatedCompHp = CompHp + fireLizardHP
        label6 = Label(frame2, image = imgFirelizard)
        label6.pack()
    
    elif CompPokemon == imgPlantWithLegs:
        CompPokemonAttacks = plantWithLegsMoves
        updatedCompHp = CompHp + PlantWIthLegsHP
        label7 = Label(frame2, image = imgPlantWithLegs)
        label7.pack()
    
    elif CompPokemon == imgWaterTurtle:
        CompPokemonAttacks = waterTurtleMoves
        updatedCompHp = CompHp + WaterTurtleHP
        label8 = Label(frame2, image = imgWaterTurtle)
        label8.pack()
    
    elif CompPokemon == imgPlotArmourRat:
        CompPokemonAttacks = plotArmourRatMoves
        updatedCompHp = CompHp + PlotArmourRatHp
        label9 = Label(frame2, image = imgPlotArmourRat)
        label9.pack()
 
    #Set up Hp box's
    while PlayerHp and updatedCompHp > 0:
        playerHpBox = Label(window2, text=PlayerHp, fg='blue', font=("Helvetica", 20))
        playerHpBox.place(x=60, y=600)
        CompHpBox = Label(window2, text=updatedCompHp, fg='red', font=("Helvetica", 20))
        CompHpBox.place(x=1800, y=50)
    return updatedCompHp

    def firespit():
        updatedCompHp -= fireLizardMoves.get("Firespit")
        return updatedCompHp
    return firespit
    
def battle_start_Plant_with_Legs():
    window1.withdraw()

def battle_start_Water_Turtle():
    window1.withdraw()

def battle_start_Plot_Armour_Rat():
    window1.withdraw()

def end_program():
    menu.destroy()
    window1.destroy()

#Create button
btn_main_menu = tk.Frame(menu, relief=tk.RAISED, bd=10)
btn_start = tk.Button(btn_main_menu, text="Start", command=choose_your_character)
btn_quit = tk.Button(btn_main_menu, text="Quit", command=end_program)

btn_choose_character = tk.Frame(window1, relief=tk.RAISED, bd=10)
btn_fireLizard = tk.Button(btn_choose_character, text="That Fire Lizard", command=battle_start_fire_Lizard)
btn_waterTurtle = tk.Button(btn_choose_character, text="Water Turtle", command=battle_start_Water_Turtle)
btn_plantWithLegs = tk.Button(btn_choose_character, text="Plant with Legs", command=battle_start_Plant_with_Legs)
btn_PlotArmourRat = tk.Button(btn_choose_character, text="Rat with Plot Armout", command=battle_start_Plot_Armour_Rat)

btn_fireLizardAttacks = tk.Frame(window2, relief=tk.RAISED, bd=10)
btn_FireSpit = tk.Button(btn_fireLizardAttacks, text="Fire Spit", command = battle_start_fire_Lizard.firespit())
btn_wingbash = tk.Button(btn_fireLizardAttacks, text="Wing Bash", command=CompHp - fireLizardMoves.get("wingbash"))
btn_bite = tk.Button(btn_fireLizardAttacks, text="Bite", command=CompHp - fireLizardMoves.get("bite"))
btn_flamethrower = tk.Button(btn_fireLizardAttacks, text="flamethrower", command=CompHp - fireLizardMoves.get("flamethrower"))

btn_PlantWithLegsAttacks = tk.Frame(window3, relief=tk.RAISED, bd=10)
btn_Sit = tk.Button(btn_PlantWithLegsAttacks, text="Sit")
btn_treebash = tk.Button(btn_PlantWithLegsAttacks, text="Tree bash")
btn_stomp = tk.Button(btn_PlantWithLegsAttacks, text="stopm")
btn_naturepower = tk.Button(btn_PlantWithLegsAttacks, text="nature power")

#Position & Set Size of Buttons
btn_start.grid(row=0, column=0, sticky="ew", padx=400, pady=5)
btn_quit.grid(row=0, column=1, sticky="ew", padx=800, pady=5)
btn_main_menu.grid(row=0, column=0, sticky="sw")

btn_fireLizard.grid(row=0, column=0, sticky="ew", padx=87.5, pady=5)
btn_plantWithLegs.grid(row=0, column=1, sticky="ew", padx=175, pady=5)
btn_waterTurtle.grid(row=0, column=3, sticky="ew", padx=262.5, pady=5)
btn_PlotArmourRat.grid(row=0, column=4, sticky="ew", padx=350, pady=5)
btn_choose_character.grid(row=0,column=0, sticky="sw")

btn_FireSpit.grid(row=0, column=0, sticky="ew", padx=87.5, pady=5)
btn_wingbash.grid(row=0, column=1, sticky="ew", padx=175, pady=5)
btn_bite.grid(row=0, column=2, sticky="ew", padx=262.5, pady=5)
btn_flamethrower.grid(row=0, column=3, sticky="ew", padx=350, pady=5)
btn_fireLizardAttacks.grid(row=1,column=0, sticky="sw")

btn_Sit.grid(row=0, column=0, sticky="ew", padx=87.5, pady=5)
btn_treebash.grid(row=0, column=1, sticky="ew", padx=175, pady=5)
btn_stomp.grid(row=0, column=2, sticky="ew", padx=262.5, pady=5)
btn_naturepower.grid(row=0, column=3, sticky="ew", padx=350, pady=5)
btn_PlantWithLegsAttacks.grid(row=1,column=0, sticky="sw")

#LOOP
menu.mainloop()