powers of two

#the goal of this app is to get the user to put in a power of two under 512 and then count up in powers of two until you 
#get to 512, outputting the results along the way.  

import math 

def powersOfTwo(x): 
	isAPowerOfTwo = not(x == 0) and not(x & (x - 1)); #test to see if you have a power of two 
	#the way this works is 
		#step 1 make sure we've not got 0 
		#step 2 and make sure that you've got a legit power of 2. This is a bitwise AND operator 
		# Bitwise operator works on bits and performs bit by bit operation. Assume if a = 60; and b = 13; Now in binary format they will be as follows  
		#a = 0011 1100
		#b = 0000 1101
		#-----------------
		#a&b = 0000 1100
		#it compares which bits are the same and gives us a new number based on just the matching bits 
		#think it through let's take the number 9  
		
		#00001001 (9)
		#00001000 (if we subtract 1 we get 8) 
		#----------
		#00001000 if we take their bitwise 'AND' value we get 8 
		#this returns a false from our not(8) operation. Why? only not(0) evaluates to true. 0 = false in computing so if you flip false you get true. this expression only is true when you do not have 0 and you do not return a value that's larger than 0. why? 
		#00001000 & (8 a power of tw0)
		#00000111	(minus 1 is 7)
		#----------
		#00000000 we get 0! Magics! So much magics! it's because any power of two will turn on all the switches behind it to equal the largest possible value 
		#WITCHCRAFT! Unholy bit magic!  
		#Does this & operation look familiar? It should- it's an and gate from hardware!! HOLY SHIT MIND BLOW! Guess what? An ~ binary ones compoent operator is a NAND gate. Yep - it's all the same. :D 

	if(isAPowerOfTwo ==True and x <= 512):  #test to make sure it's under 512 if it's a power of two 
		print("you entered " + str(x)) #tell the user were we're starting our count from  
		while(x < 512): 
			x = x << 1 #bitshift x to the left until we hit 512 :D Same thing as in the much longer to read form of the code 

			print(x) #print ouot the value 

	elif (isAPowerOfTwo):  #else tell the user it's over 512 and a power of two 
		print(str(x) + " isn't under 512")
	else: #else tell the user it's not a power of two at all  
		print(str(x) + " is not a power of Two")

####################### 
#this is the main loop for the application 

ran = False  
while(ran == False): 
	try: 
		num = raw_input ("Enter a power of Two up to 512: ")
		num = int(num) 
		powersOfTwo(num) 
		ran = True
	except ValueError: 
		print "Oops!  That was no valid number.  Try again..."