code: def mandel(x, y, max_iters):
      """
      Given the real and imaginary parts of a complex number,
      determine if it is a candidate for membership in the Mandelbrot
      set given a fixed number of iterations.
      """
      i = 0
      c = complex(x, y)
      z = 0.0j
      for i in range(max_iters):
          z = z * z + c
          if (z.real * z.real + z.imag * z.imag) >= 4:
              return i
  
      return 255
  
file_path: holoviews/examples/gallery/apps/bokeh/mandelbrot.py
imports: import numpy
  import holoviews
  from holoviews import opts
  from holoviews.streams import RangeXY
  from numba import jit
label_desc: Use image node_id 1 for calling a global function with example usage: mandel(x, y, max_iters) and returns: int, i