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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _remove_whitespace(text):
 """Remove excess whitespace from the ends of a given input string."""

        # while True:
        #     old_text = text
        #     text = text.replace('  ', ' ')
        #     if text == old_text:
        #         return text
        non_spaces = re.finditer(r'[^ ]', text)

        if not non_spaces:
            return text

        first_non_space = non_spaces.next()
        first_non_space = first_non_space.start()

        last_non_space = None
        for item in non_spaces:
            last_non_space = item

        if not last_non_space:
            return text[first_non_space:]
        else:
            last_non_space = last_non_space.end()
            return text[first_non_space:last_non_space]