我安装了gnuradio。但是当我想使用gnuradio-companion时， 我有错误：
Traceback (most recent call last):
File "/usr/local/bin/gnuradio-companion", line 99, in <module>
run_main()
File "/usr/local/bin/gnuradio-companion", line 87, in run_main
from gnuradio.grc.main import main
ImportError: No module named main
我该如何改善呢？