code: def calculate_one_cvert(self, t):
      vert = self.verts[t]
      return self.color(vert[0], vert[1], vert[2], self.t_set[t], None)
  
file_path: sympy/sympy/plotting/pygletplot/plot_curve.py
imports: import pyglet.gl
  from sympy.core import S
  from sympy.plotting.pygletplot.plot_mode_base import PlotModeBase
label_desc: Use image node_id 3 for calling the PlotCurve obj's underlying member method code with example usage: obj.calculate_one_cvert(t) and returns: self