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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 read_dictionary_file(dictionary_path):
 """Return all words in dictionary file as set."""

    try:
        return _user_dictionary_cache[dictionary_path]
    except KeyError:
        if dictionary_path and os.path.exists(dictionary_path):
            with open(dictionary_path, "rt") as dict_f:
                words = set(re.findall(r"(\w[\w']*\w|\w)",
                                       " ".join(dict_f.read().splitlines())))
                return words

        return set()