code: def validate_scale_values(scale):
      """
      Validates scale values from a colorscale
  
      :param (list) scale: a strictly increasing list of floats that begins
          with 0 and ends with 1. Its usage derives from a colorscale which is
          a list of two-lists (a list with two elements) of the form
          [value, color] which are used to determine how interpolation weighting
          works between the colors in the colorscale. Therefore scale is just
          the extraction of these values from the two-lists in order
      """
      if len(scale) < 2:
          raise exceptions.PlotlyError(
              "You must input a list of scale values "
              "that has at least two values."
          )
  
      if (scale[0] != 0) or (scale[-1] != 1):
          raise exceptions.PlotlyError(
              "The first and last number in your scale must be 0.0 and 1.0 "
              "respectively."
          )
  
      if not all(x < y for x, y in zip(scale, scale[1:])):
          raise exceptions.PlotlyError(
              "'scale' must be a list that contains a strictly increasing "
              "sequence of numbers."
          )
  
imports: from __future__ import absolute_import
  import decimal
  from numbers import Number
  import six
  from _plotly_utils import exceptions
  from .None import qualitative, sequential, diverging, cyclical, cmocean, colorbrewer, carto, plotlyjs
label_desc: Use image node_id 6 for calling a global function with example usage: validate_scale_values(scale) without return types