Fibonacci Sequence

FibonacciSequence.py

#Fibonacci Sequence
#Have fun, Dr. Half-Shot

#Checks if a number is an integer.
def IsInt(val):
	try:
		int(val)
	except:
		return False
	return True

def Main():
	CountTo = input("Enter a number to count to (non-integer for forever):")
	if IsInt(CountTo): #If the number is an integer
		print("Counting from 0 to", CountTo) #Give the user a friendly message.
		Sequence(int(CountTo))# Yes > Use specfied number to start the sequence.
	else:
		print("End of it.")
		Sequence(-1) #Runs indefinately

def Sequence(val):
	x = 0 #First
	y = 1 #Before nOne
	print("0", end="") #Add a zero, its proper.
	while(x < val or val == -1):
		new = x + y
		y = x
		x = new
		print("",x, end="")
	print("\nFinished")
		

if __name__ == "__main__":
	Main()