You better use in
if len(original) and original.isalpha():
word = original.lower()
first = word[0]
print first
if first in ('a','e','i','o','u'):
print "vowel"
else:
print "consonant"
also you are doing it wrong, if you are trying to use OR clause you must use like this BUT it's not the better pythonic way:
if first =='a' or first =='e' or first =='i' or first =='o' or first =='u':
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