Nushell has the in operator to check if a value is an element of list.
With the same in operator you can check if a string is a substring of another string.
And finally you can use the in operator to check if a key is in a record.
When you use the operator the value you want to check is defined before the operator and the list, other string or record is defined after the operator.
The not-in operator is the opposite of the in operator and checks if a value is not in list or other string or key in a record.
It is also possible to use the has and not-has operators to do the same checks, but the value you want to check is set after the operator.
The list, other string or record is set before the operator.
