Your function should return a multiline string of unique lowercase letters in alphabetical order. The characters should be placed in a form of hollow rhombus (diamond), along its edges, starting from the top vertex.

For this purpose you are given three values (for their constraints see Preconditions):

• side - number of letters in each side of the rhombus;
• length - total number of letters you should use;
• cw - clockwise flag, which shows in what direction the letters must go (if True - letters should be placed in clockwise direction).

If it's not enough length to complete the form, complement it with "*". The rhombus should not have white spaces at the right. Here is an example with arguments and expected result:

Input: Three arguments: side as integer (int), length as integer (int) and clockwise flag as logic (bool).

Output: Multiline string (str).

Examples:

assert hollow_diamond(3, 8, True) == "  a\n h b\ng   c\n f d\n  e"
assert hollow_diamond(3, 6, False) == "  a\n b *\nc   *\n d f\n  e"
assert (
    hollow_diamond(4, 10, False) == "   a\n  b *\n c   *\nd     j\n e   i\n  f h\n   g"
)
assert (
    hollow_diamond(5, 16, True)
    == "    a\n   p b\n  o   c\n n     d\nm       e\n l     f\n  k   g\n   j h\n    i"
)

Preconditions:

• 26 >= length >= 0;
• side > 1;
• (side-1)*4 >= length.