The error: bad marshal data
When you try to install a python package you get the error:
Traceback (most recent call last): from sqlalchemy.ext.declarative import declarative_base File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/ext/declarative/__init__.py", line 8, in <module> from .api import declarative_base, synonym_for, comparable_using, \ File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/ext/declarative/api.py", line 11, in <module> from ...orm import synonym as _orm_synonym, \ File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/orm/__init__.py", line 17, in <module> from .mapper import ( File "/usr/local/lib/python2.7/dist-packages/sqlalchemy/orm/mapper.py", line 27, in <module> from . import properties ValueError: bad marshal data (unknown type code)
Check the traceback path and delete all the pycs files recursively:
find /PATH_ON_TRACEBACK -name '*.pyc' -delete
In our case the path was "/usr", howevery it could be inside your virtualenv.