$16.$ Implement fixed$\_$points

Read the specification of the function fixed$\_$points in the module funcs. Implement this function according to its specification. This is a function where it is particularly helpful to look at the examples and test cases.

When you have implemented the function, test your answer with the test script. You should now pass all tests.def fixed$\_$points$($tup$)$:

$"""$

Returns a copy of tup, including only the "fixed points".

A fixed point of a tuple is an element that is equal to its position in the tuple.

For example $0$ and $2$ are fixed points of $(0,3,2).$ The fixed points are returned in

the order that they appear in the tuple.

Examples:

fixed$\_$points$((0,3,2))$ returns $(0,2)$

fixed$\_$points$((0,1,2))$ returns $(0,1,2)$

fixed$\_$points$((2,1,0))$ returns $(1,)$

Parameter tup: the tuple to copy

Precondition: tup is a tuple of ints

$"""$