when i run env.render
i get this error
AssertionError: No 'v' attribute found in ShaderProgram(id=4).
Valid attibutes are: {'colors': Attribute('colors', program=4, location=1, count=4, format=f), 'position': Attribute('position', program=4, location=0, count=3, format=f), 'tex_coords': Attribute('tex_coords', program=4, location=2, count=3, format=f)}.