Define a function myinsert(seq,index,item) that inserts item at position index of the list seq and returns the new list.

def myinsert(seq, index, item):
    """Insert item at index of seq.

    >>> myinsert([1, 2, 3], 1, 4)
    [1, 4, 2, 3]
    >>> myinsert([1, 2, 3], 5, 4)
    [1, 2, 3]
    >>> myinsert([True, False], 2, None)
    [True, False, None]
    >>> myinsert([],0,1)
    [1]
    >>> myinsert([1,4],1,[2,3])
    [1, [2, 3], 4]
    """