Let's Rock Example Error

[ssungho98]

Hello! I followed all the installation instructions(except GLRenderer) and faced the following error message while trying Let's Rock first step.
"""
File "fluidlab/run.py", line 10, in
from fluidlab.optimizer.solver import solve_policy
File "/home/sungho/FluidLab/fluidlab/optimizer/init.py", line 1, in
from .solver import Solver
File "/home/sungho/FluidLab/fluidlab/optimizer/solver.py", line 7, in
from fluidlab.fluidengine.taichi_env import TaichiEnv
File "/home/sungho/FluidLab/fluidlab/fluidengine/taichi_env.py", line 7, in
from fluidlab.fluidengine.renderers import *
File "/home/sungho/FluidLab/fluidlab/fluidengine/renderers/init.py", line 4, in
from .gl_renderer import GLRenderer
File "/home/sungho/FluidLab/fluidlab/fluidengine/renderers/gl_renderer.py", line 10, in
from .gl_renderer_src import flex_renderer
ImportError: cannot import name 'flex_renderer' from 'fluidlab.fluidengine.renderers.gl_renderer_src' (unknown location)
"""

Could you take a look into this?