On Wed, Jan 7, 2015 at 2:12 PM, John Ladasky <john_lada...@sbcglobal.net> wrote: > If I execute "import my_svr" in an iPython interpreter, everything works as I > think that I should expect: -snip- > However, a nearly-identical program in the parent folder fails (note that all > I change is the relative path to the file): > Traceback (most recent call last): > File "reload test different directory.py", line 6, in <module> > model = load(f) > ImportError: No module named 'model' > > > Do I need to "import my_svr.model as model" then? Adding that line changes > nothing. I get the exact same "ImportError: No module named 'model'". > > Likewise for "import my_svr", "from my_svr import *", or even "from > my_svr.model import SVRModel". > > It is clear that I'm failing to understand something important.
in the first case, the model module was available as a top-level module, "model". Pickles referenced that module when serialized. In the second case, the model module was available as a submodule of the top level my_svr package. So any pickles serialized from there would use my_svr.model to refer to the model module. There *is* no model module in this second case, so deserializing fails. If you never run model directly, and only ever import it or run it as my_svr.model, then you will be fine, and pickles will all serialize and deserialize the same way. For example, instead of python -i my_svr/model.py, you can use python -im my_svr.model . (or ipython -im my_svr.model). P.S. don't use pickle, it is a security vulnerability equivalent in severity to using exec in your code, and an unversioned opaque schemaless blob that is very difficult to work with when circumstances change. > I do not have any circular import dependencies; however, some of the files in > my package do need to import definitions from files earlier in my data > pipeline. In order to make everything work inside the module, as well as > making a parent-folder "import my_svr" work from a iPython, I find myself > needing to use statements like these inside my training.py program: > > > try: > from model import * > from sampling import * > except ImportError: > from .model import * > from .sampling import * > > > This bothers me. I don't know whether it is correct usage. I don't know > whether it is causing my remaining ImportError problem. This is a symptom of the differing ways you are importing these modules, as above. If you only ever run them and import them as my_svr.blahblah, then only the second set of imports are necessary. P.S. don't use import *, and if you do use import *, don't use more than one per file -- it makes it really hard to figure out where a given global came from (was it defined here? was it defined in model? was it defined in sampling?) I hope that resolves all your questions! -- Devin -- https://mail.python.org/mailman/listinfo/python-list
