I'm learning to program and I've chosen Python as my first language. I've written a function to count vowels in a string and print the number of occurrences of each of them. Please review my code and let me know if there is a better way of writing the same as I believe there is always room for improvement.
vowels = 'aeiou'
def vowel_count(txt):
for vowel in vowels:
if vowel in txt:
print vowel, txt.count(vowel)
txt_input = raw_input('Enter text: ').lower()
vowel_count(txt_input)