code: def _get_subplot_number(subplot_val):
      """
      Extract the subplot number from a subplot value string.
  
      'x3' -> 3
      'polar2' -> 2
      'scene' -> 1
      'y' -> 1
  
      Note: the absence of a subplot number (e.g. 'y') is treated by plotly as
      a subplot number of 1
  
      Parameters
      ----------
      subplot_val: str
          Subplot string value (e.g. 'scene4')
  
      Returns
      -------
      int
      """
      match = _subplot_re.match(subplot_val)
      if match:
          subplot_number = int(match.group(1))
      else:
          subplot_number = 1
      return subplot_number
  
file_path: holoviews/holoviews/plotting/plotly/util.py
imports: import copy
  import re
  import numpy
  from plotly import colors
  from ...core.util import isfinite, max_range
  from ..util import color_intervals, process_cmap
label_desc: Use image node_id 1 for calling a global function with example usage: _get_subplot_number(subplot_val) and returns: subplot_number