Traceback (most recent call last):


 "./run_electrum", line 377, in <module>

pid = os.fork()
AttributeError: module 'os' has no attribute 'fork'```

Traceback (most recent call last):


 "<stdin>", line 1, in <module>


 "/home/jan/.pyenv/versions/3.7.4/lib/python3.7/site-packages/sympy/matrices/expressions/blockmatrix.py", line 91, in _blockmul

self.colblocksizes == other.rowblocksizes):


 "/home/jan/.pyenv/versions/3.7.4/lib/python3.7/site-packages/sympy/matrices/expressions/blockmatrix.py", line 80, in colblocksizes

return [self.blocks[0, i].cols for i in range(self.blockshape[1])]


 "/home/jan/.pyenv/versions/3.7.4/lib/python3.7/site-packages/sympy/matrices/expressions/blockmatrix.py", line 80, in <listcomp>

return [self.blocks[0, i].cols for i in range(self.blockshape[1])]
AttributeError: 'Zero' object has no attribute 'cols'
