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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 substring_search(word, collection):
 """Find all matches in the `collection` for the specified `word`. If `word` is empty, returns all items in `collection`. :type word: str :param word: The substring to search for. :type collection: collection, usually a list :param collection: A collection of words to match. :rtype: list of strings :return: A sorted list of matching words from collection. """

    return [item for item in sorted(collection) if item.startswith(word)]