Errors pop out when run the pytest

[Jackwin]

Hi all,
I cloned the Lassen from the master branch and everything seems Okay following the installation steps. But when run the 'pytest tests' command, many errors appear. The summary error info is shown as follows. Is there any extra job that should be done? Thanks ahead.

======================================================================================================== short test summary info ========================================================================================================
ERROR tests/test_complex.py - TypeError: 'NoneType' object is not subscriptable
ERROR tests/test_mapper.py - TypeError: 'NoneType' object is not subscriptable
ERROR tests/test_micro.py - Exception: Error occured when executing m.circuit.combinational function RegisterMode_comb, see above
ERROR tests/test_pe.py - Exception: Error occured when executing m.circuit.combinational function RegisterMode_comb, see above
ERROR tests/test_reset.py - Exception: Error occured when executing m.circuit.combinational function RegisterMode_comb, see above
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Interrupted: 5 errors during collection !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
===================================================================================================== 1 warning, 5 errors in 2.54s ==================================================================================================