class_docstr: A single color
  
  Parameters
  ----------
  color : str | tuple
      If str, can be any of the names in ``vispy.color.get_color_names``.
      Can also be a hex value if it starts with ``'#'`` as ``'#ff0000'``.
      If array-like, it must be an 1-dimensional array with 3 or 4 elements.
  alpha : float | None
      If no alpha is not supplied in ``color`` entry and ``alpha`` is None,
      then this will default to 1.0 (opaque). If float, it will override
      the alpha value in ``color``, if provided.
  clip : bool
      If True, clip the color values.
class_docstr_tok: ["A","single","color","Parameters","--","--","--","--","--","color",":","str","|","tuple","If","str",",","can","be","any","of","the","names","in","``","vispy.color.get_color_names","``",".","Can","also","be","a","hex","value","if","it","starts","with","``","'","#","'","``","as","``","'","#","ff0000","'","``",".","If","array-like",",","it","must","be","an","1-dimensional","array","with","3","or","4","elements",".","alpha",":","float","|","None","If","no","alpha","is","not","supplied","in","``","color","``","entry","and","``","alpha","``","is","None",",","then","this","will","default","to","1.0","(","opaque",")",".","If","float",",","it","will","override","the","alpha","value","in","``","color","``",",","if","provided",".","clip",":","bool","If","True",",","clip","the","color","values","."]
docstr: Boolean indicating whether the color is invisible.
docstr_tok: ["Boolean","indicating","whether","the","color","is","invisible","."]
code: def is_blank(self):
      """Boolean indicating whether the color is invisible."""
      return self.rgba[3] == 0
  
imports: from __future__ import division
  import numpy
  from copy import deepcopy
  from ..util import logger
  from ._color_dict import _color_dict
  from .color_space import _hex_to_rgba, _rgb_to_hex, _rgb_to_hsv, _hsv_to_rgb, _rgb_to_lab, _lab_to_rgb
label_desc: Use image node_id 11 for calling the Color obj's underlying member method code with example usage: obj.is_blank() and returns: unknown