code: def use_gl(target=None):
      """Let Vispy use the target OpenGL ES 2.0 implementation
  
      Also see ``vispy.use()``.
  
      Parameters
      ----------
      target : str
          The target GL backend to use. Default gl2 or es2, depending on the platform.
  
      Available backends:
      * gl2 - Use ES 2.0 subset of desktop (i.e. normal) OpenGL
      * gl+ - Use the desktop ES 2.0 subset plus all non-deprecated GL
        functions on your system (requires PyOpenGL)
      * es2 - Use the ES2 library (Angle/DirectX on Windows)
      * pyopengl2 - Use ES 2.0 subset of pyopengl (for fallback and testing)
      * dummy - Prevent usage of gloo.gl (for when rendering occurs elsewhere)
  
      You can use vispy's config option "gl_debug" to check for errors
      on each API call. Or, one can specify it as the target, e.g. "gl2
      debug". (Debug does not apply to 'gl+', since PyOpenGL has its own
      debug mechanism)
      """
      target = target or default_backend.__name__.split(".")[-1]
      target = target.replace("+", "plus")
  
      # Get options
      target, _, options = target.partition(" ")
      debug = config["gl_debug"] or "debug" in options
  
      # Select modules to import names from
      try:
          mod = __import__(target, globals(), level=1)
      except ImportError as err:
          msg = 'Could not import gl target "%s":\n%s' % (
              target,
              str(err),
          )
          raise RuntimeError(msg)
  
      # Apply
      global current_backend
      current_backend = mod
      _clear_namespace()
      if "plus" in target:
          # Copy PyOpenGL funcs, extra funcs, constants, no debug
          _copy_gl_functions(mod._pyopengl2, globals(), debug=debug)
          _copy_gl_functions(mod, globals(), True, debug=debug)
      else:
          _copy_gl_functions(mod, globals(), debug=debug)
  
file_path: vispy/vispy/gloo/gl/__init__.py
imports: from __future__ import division
  import os
  from ...util import config, logger
  from ._constants import *
  from ._proxy import BaseGLProxy
  from .None import gl2
label_desc: Use image node_id 1 for calling a global function with example usage: use_gl(target) without return types