How to use the .isalpha() function correctly

[Luke Tomaneng]

Here a very small program that I wrote for Codecademy. When I finished, Codecademy acted like it was correct, but testing of this code revealed otherwise.
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print 'Welcome to the Pig Latin Translator!'

# Start coding here!
raw_input("Enter a word:")
original = str(raw_input)
if len(original) > 0 and original.isalpha():
    print original
else:
    print "empty"
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No matter what I type in, the result is "empty." What do I need to do in order for it to accept words?