No module named (import error Python 2.7)

Question

I'm trying to solve exercise 25 in Learn Python The Hard Way by following each step but I keep getting this error:

>>> import ex25
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ImportError: No module named ex25

I copy-pasted the code from the book's site to Gedit (Linux text editor) but it doesn't seem to be a typo.

   def break_words(stuff):
        """This function will break up words for us."""
        words = stuff.split(' ')
        return words

    def sort_words(words):
        """Sorts the words."""
        return sorted(words)

    def print_first_word(words):
        """Prints the first word after popping it off."""
        word = words.pop(0)
        print word

    def print_last_word(words):
        """Prints the last word after popping it off."""
        word = words.pop(-1)
        print word

    def sort_sentence(sentence):
        """Takes in a full sentence and returns the sorted words."""
        words = break_words(sentence)
        return sort_words(words)

    def print_first_and_last(sentence):
        """Prints the first and last words of the sentence."""
        words = break_words(sentence)
        print_first_word(words)
        print_last_word(words)

    def print_first_and_last_sorted(sentence):
        """Sorts the words then prints the first and last one."""
        words = sort_sentence(sentence)
        print_first_word(words)
        print_last_word(words)

Answer 1

@Padraic Cunningham and @James Mills are asking the right questions, you are just getting an import error, nothing to allude to a code error. You need to make sure that the file exist in the directory that you are working in. Remember that it is case sensitive.

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