`My`

    @Contract(pure = true)i
    boolean contains(
        Object o
    )
    throws IOException

From interface: | `java.util.Collection` Returns `true` if this collection contains the specified element. More formally, returns `true` if and only if this collection contains at least one element `e` such that `(o==null ? e==null : o.equals(e))`.
Overrides: | `contains` in interface `Collection` `contains` in interface `I`
Params: | `o` – element whose presence in this collection is to be tested
Returns: | `true` if this collection contains the specified element
Throws: | `NullPointerException` – before if the specified element is null and this collection does not permit null elements (optional) after IOException