Simple Word Counter in Python 3

#NOTE : I used Notepad++ as my text editor.

#Import
import sys
import random
import os

#Functions

def startsWith(line):
        b = list(line)
        return str(b[0])

def isCommand(line):
        if line == str(command[0]) or line == str(command[1]) or line == str(command[2]) or line == str(command[3]) or line == str(command[4]) or line == str(command[5]) or line == str(command[6]):
                return True
        else:
                return False

#Variables
command = ["/reset","/quit","/example", "/help", "/lastline", "/lines", "/about"]
all_lines = []

#Main Program
print("Welcome to Word Counter 2.0")
while True:
    #Very important stuff
    line = input("\n Enter a line : ")
    words = line.split()
    total_words = len(words)
    AlfaNum_characters = list(line)
    Symbol_characters = list(line)      #Notice how these three are the same. But why?
    Space_characters = list(line)

    #Things to remove (These will help us find the number of letters, numbers, symbols or spaces in a line. PS. )
    Symbols_to_remove = list("!@#$%^&*()-=_+[]{}:;<>/,.|`~?\\")*len(line)
    AN_to_remove = list("QWERTYUIOPASDFGHJKLZXCVBNMqwertyuiopasdfghjklzxcvbnm1234567890")*len(line)
    spaces_to_remove = [" "]*len(line)

    #Note : I know this is not the best way to count them, but that's your problem. *evil face*

    #Remove symbols form the letters and numbers list of our current line
    for i in Symbols_to_remove:
        try:
            AlfaNum_characters.remove(i)
        except:
            continue

    #Remove letters and numbers form the symbols list of our current line
    for i in AN_to_remove:
        try:
            Symbol_characters.remove(i)
        except:
            continue

    #Remove all spaces from both of those lists
    for i in spaces_to_remove:
        try:
            AlfaNum_characters.remove(i)
            Symbol_characters.remove(i)
        except:
            continue

    #Remove everything except for spaces
    for i in AN_to_remove:
        try:
            Space_characters.remove(i)
        except:
            continue
    for i in Symbols_to_remove:
        try:
            Space_characters.remove(i)
        except:
            continue

    if len(words) == 1:
        SorP_W = "Word"
    else:
        SorP_W = "Words"

    #Not Commands
    if startsWith(line) != "/":
        print(line)
        print(total_words, SorP_W)
        print(len(AlfaNum_characters), "Letter(s) and/or Number(s)")
        print(len(Symbol_characters), "Symbol(s)")
        print(len(Space_characters), "Space(s)")

        all_lines.append(line)

    #Commands
    if startsWith(line) == "/" and isCommand(line) == False:
        print("The command you entered is not valid. Please use /help to view all the commands. @Creator")

    elif line == command[0]:
        os.system('cls')
        print("Welcome to Word Counter 2.0")
        all_lines = []

    elif line == command[1]:
        sys.exit()

    elif line == command[2]:
        #Will count only words. You can add other ones if you want.
        examples = ["Mary has a pig. It is named Mary.", "John met Steve and Steve met Dad.", "Dad is a Jew. EW!", "You are the 10000000th visitor!. This is no joke. >>>CLICK HERE TO FIND OUT MORE<<<", "Is he called Steve or Steven? Who cares, he's gay anyway.", "David, why are you so mean?, - said Ann. What do you mean?, - responded David", "There's something odd about this painting. It has an even number of bananas and peaches. Hmm..."]
        ex_num = random.randint(0,len(examples))
        ex_display = examples[ex_num]
        ex_display_words_num = len(ex_display.split(" "))
        if ex_display_words_num == 1:
            SorP_W = "Word"
        else:
            SorP_W = "Words"
        print(ex_display)
        print(ex_display_words_num, SorP_W)

    elif line == command[3]:
        print("Here's a list of our commands : /help, /reset, /quit, /example, /lastline, /lines, /about. To add : /file, /sentences, /??? (Top Secret), /jokes")

    elif line == command[4]:
        try:
            print("The last line you entered was :", all_lines[len(all_lines)-1])
        except:
            print("No previous line found.")

    elif line == command[5]:
        if all_lines != []:
            print("The lines you entered so far are :")
            line_order = 1
            for i in all_lines:
                print(str(line_order)+".", i)
                line_order += 1
        else:
            print("No previous line found.")

    elif line == command[6]:
        print("This is a simple program that I wrote in Python. This is the second version (The first one was horrible). Some time after finishing the first one, I decided to make it once again starting from 0. It was quite fun making the code sexier. The program does exactly what you think it does, but also finds the number of letters, numbers and symbols (letters and numbers are counted together because I WANT SO). Feel free to use this program as you wish (OMG will you finish already?). \n KTHXBAI")