docs: def dumb_relative_half_prime(n, divisor = None):
      '''A dumb brute-force algorithm to find a relative prime for n which is approximately n/2 through n/5.
         It is used for generating spaced colors.
         Written on a Friday evening. Do not judge!
      '''
      if n < 1 or not isinstance(n, int):
          raise Exception('n must be a positive non-zero integer.')
      elif n < 7:
          return dumb_relative_prime_const[n]
      elif n < 10:
          divisor = 2.0
      if not divisor:
          if n <= 20:
              divisor = 3.0
          elif n <= 30:
              divisor = 4.0
          else:
              divisor = 5.0
      m = int(n / divisor)
      while m > 1:
          if fractions.gcd(n, m) == 1:
              return m
          m -= 1
      if divisor > 2.0:
          return dumb_relative_half_prime(n, divisor - 1.0)