72    answer = number1 + number2
 73    print("The answer is: " + str(answer))
 74    with open('Log.txt', 'a') as f:
 75        f.writelines(str(number1)  + str(operator1) + str(number2) + '=' + str(answer) + '\n') 76elif operator1 == '-':
 77    answer = number1 - number2
 78    print(answer)

 39        print("You have to type a number!")
 40        sys.exit()
 41operator1 = input("Type out your operator: ")
 42    #operator1 == '+' or '-' or '*' or '/' or '^' or 'sqrt' or 'log' or 'sin' or 'cos' or 'tan' or ('tan^-1') or ('cos^-1') or ('sin^-1') 43
 44if operator1 in ch:
 45    pass

  8ch = ['+' , '-' , '*' , '/' , '^' , 'sqrt' , 'log' , 'sin' , 'cos' , 'tan' , 'tan^-1' ,'cos^-1' ,'sin^-1', '!']
  9ch_trig = ['sin' , 'cos' , 'tan' , 'tan^-1' ,'cos^-1' ,'sin^-1', 'sqrt' , 'log'  , '!']
 10pi = 3.1415926535897932384626433832795028841971693993751058209749445923078164062862089986280348253421170679
 11e = 2.7182818284590452353602874713526624977572470936999595749669676277240766303535475945713821785251664274 12
 13print("Welcome to the calculator!")
 14print("These are the available operations:")

  7#ch_pi =['pi' , 'π']
  8ch = ['+' , '-' , '*' , '/' , '^' , 'sqrt' , 'log' , 'sin' , 'cos' , 'tan' , 'tan^-1' ,'cos^-1' ,'sin^-1', '!']
  9ch_trig = ['sin' , 'cos' , 'tan' , 'tan^-1' ,'cos^-1' ,'sin^-1', 'sqrt' , 'log'  , '!']
 10pi = 3.1415926535897932384626433832795028841971693993751058209749445923078164062862089986280348253421170679 11e = 2.7182818284590452353602874713526624977572470936999595749669676277240766303535475945713821785251664274
 12
 13print("Welcome to the calculator!")

  5from xml.dom.pulldom import IGNORABLE_WHITESPACE
  6# lists for confirming validity of inputs
  7#ch_pi =['pi' , 'π']
  8ch = ['+' , '-' , '*' , '/' , '^' , 'sqrt' , 'log' , 'sin' , 'cos' , 'tan' , 'tan^-1' ,'cos^-1' ,'sin^-1', '!']  9ch_trig = ['sin' , 'cos' , 'tan' , 'tan^-1' ,'cos^-1' ,'sin^-1', 'sqrt' , 'log'  , '!']
 10pi = 3.1415926535897932384626433832795028841971693993751058209749445923078164062862089986280348253421170679
 11e = 2.7182818284590452353602874713526624977572470936999595749669676277240766303535475945713821785251664274