How to read file during module import?

Gabriel Genellina gagsl-py2 at
Fri Apr 9 18:02:45 EDT 2010

En Fri, 09 Apr 2010 18:04:59 -0300, Jeremy <jlconlin at> escribió:

> How can I locate the file during the import statement.  The supporting
> file is located in the same directory as the module, but when I import
> I get a No such file or directory error.  I could hard code the path
> to the filename, but that would make it only work on my machine.

The directory containing the current module is:

module_dir = os.path.dirname(os.path.abspath(__file__))

so you could open your supporting file using:

fn = os.path.join(module_dir, "supporting_file_name.ext")
open(fn) ...

> A related question: Can I parse the data once and keep it somewhere
> instead of reading the supporting file every time?  I tried pickling
> but that wouldn't work because I have custom classes.  (Either that or
> I just don't know how to pickle—this is a highly probable event.)

What kind of "custom classes"?
An open file, or a socket, are examples of non pickleable objects; most  
other basic built-in objects are pickleable. Instances of user-defined  
classes are pickleable if they contain pickleable attributes. Micro recipe:

# pickle some_object
with open(filename, "wb") as f:
   pickle.dump(some_object, f, -1)

# unpickle it
with open(filename, "rb") as f:
   some_object = pickle.load(f)

Try again and report any problem you encounter...

Gabriel Genellina

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