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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 simplify_types(types):
 # type: (Iterable[AbstractType]) -> List[AbstractType] """Given some types, give simplified types representing the union of types."""

    flattened = flatten_types(types)
    items = filter_ignored_items(flattened)
    items = [simplify_recursive(item) for item in items]
    items = merge_items(items)
    items = dedupe_types(items)
    # We have to remove reundant items after everything has been simplified and
    # merged as this simplification may be what makes items redundant.
    items = remove_redundant_items(items)
    if len(items) > 3:
        return [AnyType()]
    else:
        return items