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Fail python import from another folder

I am experimenting with python, mostly troubleshooting other people's code. I am trying to get a program to run, "path\folderA\program.py".
I am running the program from path\folderA
I am getting an error:
ImportError: No module named fff.ggg.ppp
program.py contains an import:
from fff.ggg.ppp import mmm
In the folder "path\folderB" there are:
"path\folderB\fff\__init__.py"
"path\folderB\fff\ggg"
folder ggg also contains __init__.py, as well as program ppp.py
From reading other posts, like Python error "ImportError: No module named" I understand that having the __init__.py makes a folder a "package" which makes imports from it possible - but it doesn't work, since I am getting an error.
This has been working for other people that worked with these projects, so there is something wrong with my setup.
I read something about the directories having to be in the sys.path. Does that mean I have to add them to the environment variable path ? That would mean adding a lot of directories to the PATH though, so it can't be.
So I also found the following:
import sys
sys.path.append( <path to FolderB> )
But that means changing the code (which has not been necessary for other people) and hard-coding a path to what it is on my local machine - which I shouldn't have to, right ?
I can't visualize it - apparently I am not supposed to change the code and hard-code the physical path to the import module - so how can a program from folderA even know to look in folderB for an import ?
How does the magic of __init__.py work ?

I can't visualize it - apparently I am not supposed to change the code
and hard-code the physical path to the import module - so how can a
program from folderA even know to look in folderB for an import ?
You are correct. Somehow you have to tell python to look for imported modules in folderB. There is no __init__.py magic that lets you import from other folders on your hard drive.
Usually, if you've got various different python packages like that, they work by being installed into python's library. That way they can imported from anywhere. This is usually accomplished by a setup.py script. Check if folderB has one. Run it with python setup.py install.
If that doesn't work, we'll need more information about how this code is structured.

Folder B must be on the sys.path, so you would either need to move mmm to A, or modify sys.path from within A (not sure if that works). __init__.py tells python that the folder is a package, so you could have folders with __init__.py within folders with __init__.py and python treats the folders inside as parts of the parent folder. Check out sympy or almost any large python library and you will find such a structure. It can also contain code to be run on import, but can also be empty.

Importing a module which have the same name with a system module

My situation is similar to one in this question... The difference is,
In our python/django project, we have a directory called utils, which keeps basic functions...
Sometimes, we need to test some modules by running thm from console like
python myproject/some_module.py
It is all good, until python tries to import something from our utils directory...
from utils.custom_modules import some_function
ImportError: No module named custom_modules
I check my python path, and our project is on the list, each folder under the project file has __init__.py files, and when i run ipython within project directory... Everything is ok, otherwise, python imports from its own utils directory...
My collegues use the sama method without any problem, but it throws ImportError on my environment... What could be the problem that all of us was missing?
UPDATE: My project directory, and each sub-drectory have __init__.py file, and i can import other modules from my project without any problem... When i am in a diffrent folder than my procekt and i run ipython, a such import have no problem...
from someothermodule.submodule imprort blahblahblah
But, when it comes to importing utils, it fails...
UPATE 2: What caused the problem was the utils directory under django folder, which is also in the python path...

See the PEP on absolute and relative imports for the semantics. You probably want
from .utils.custom_modules import some_function
if you're in a file at the top level of your package.
Edit: This can only be done from inside a package. This is for a good reason -- if you're importing something that is part of your project, then you're already treating it like a Python package, and you should actually make it one. You do this by adding an __init__.py file to project directory.
Edit 2: You've completely changed the question. It may be possible to work around the problem, but the correct thing to do is not refer to your packed the same way as a builtin package. You either need to rename utils, or make it a subpackage of another package, so you can refer to it by a non-conflicting name (like from mydjangoapp.utils.custom_modules import some_function).

I'm not going to bother telling you to try and make sure you don't name your own modules after the stdlib modules;
If you want to leave the name like this, you'll have to use something like this in everything that imports your own utils module:
import sys, imp
utils = sys.modules.get('utils')
if not utils: utils = imp.load_module('utils',*imp.find_module('utils/utils'))
However, unless there's a lot of stuff that you'd have to change after renaming it, I'd suggest you rename it.

How to import module from current non-default directory

I'm using Python 2.7. I'm rather new to the python langauge. I have two python modules - "Trailcrest.py" and "Glyph.py", both in the same folder, but not in the Python27 folder.
I need to import "Trailcrest.py" into "Glyph.py", but I am getting the message that "no such module exists".
Additionally, whatever means I use to import the module needs to not be dependent on a solid-state path. This program is cross-platform, and the path can be changed depending on the user's preferences. However, these two modules will always be in the same folder together.
How do I do this?

If you have Trailcrest.py and Glyph.py in the same folder, importing one into the other is as simple as:
import Trailcrest
import Glyph
If this does not work, there seems to be something wrong with your Python setup. You might want to check what's in sys.path.
import sys
print sys.path

To elaborate a bit on Ferdinand Beyer's answer, sys.path is a list of file locations that the default module importer checks. Some, though not all installations of python will add the current directory or the directory of the __main__ module to the path. To make sure that the paths relative to a given module are importable in that module, do something like this:
import os.path, sys
sys.path.append(os.path.dirname(__file__))
But something like that shouldn't ever make it into a "production" product. Instead, use something like distutils to install the module's package into the python site-packages directory.

This can also be achieved using the environment variable PYTHONPATH which also influences Python's search path. This can be done in a shell script so that the Python files do not need to be altered. If you want it to import from the current working directory use the . notation in bash:
export PYTHONPATH=.
python python_prog.py

python import problem

although there are many posts on the internet as well as some posts on stack overflow, I still want to ask about this nasty python "import" problem.
OK. so, the open source code organization is usually like this:
project/src/model.py;
project/test/testmodel.py
if I put the famous __init__.py in project directory and also in src/ and test/ subdirectories,
and then put "from project.src import model" for the testmodel.py.
it does not work! keep telling me that the Module named "project.src" is not found!
how can I solve the problem without changing the code structure?

You shoud not add the project directory to your pythonpath but it's parent, e.g. imagine the setup
/home/user/develop/project/src/model
You'd add /home/user/develop to PYTHONPATH
If that still doesn't work, make sure you don't have a 'project.py' insite project/src/model.

Make sure you have the parent directory of project/ on your pythonpath, rather than the project directory. If you add the project path itself, imports like import project.src will look for project/project/src.

The directory where project is located is probably not in your python path.

You can use a relative import (assuming Python 2.5+) from testmodel.py, like:
from ..src import model
However, this does not work if you're running testmodel.py as the main module.

Utilizing multiple python projects

I have a python app, that I'm developing. There is a need to use another library, that resides in different directory.
The file layout looks like this:
dir X has two project dirs:
current-project
xLibrary
I'd like to use xLibrary in currentProject. I've been trying writting code as if all the sources resided in the same directory and calling my projects main script with:
PYTHONPATH=.:../xLibrary ./current-project.py
but this does not work. I'd like to use its code base without installing the library globaly or copying it to my project's directory. Is it possible? Or if not, how should I deal with this problem.

It's generally a good programming practice to isolate packages into actual packages and treat them as such. If you're sure you'd like to continue with that approach though you can modify the search path from within python via:
import sys
sys.path.append( "<path_containing_the_other_python_files>" )
To avoid embedding absolute paths, you can use os.path.abspath(__file__) to obtain the absolute path to the currently executing .py file and follow up with a few os.path.dirname() calls to construct the proper relative path for inclusion to sys.path
A slightly altered approach that would allow you to get the best of both worlds would be to add an __init__.py file to xLibrary's directory then add the path containing 'xLibrary' to sys.path instead. Subsequent Python code could then import everything "properly" via from xLibrary import my_module rather than just import my_module which could be confusing to people accustomed to the standard package directory layout.

This depends how you use xLibrary from current-project.
If you do something like from xLibrary import module1 inside current-project, the xLibrary needs to be laid out as a Python package:
xLibrary/
xLibrary/__init__.py
xLibrary/module1.py # or whatever other modules the package consists of
In this case, you should include xLibrary's parent directory in PYTHONPATH:
PYTHONPATH=.:.. ./current-project.py
However, if xLibrary is just a collection of Python modules that you import individually (that is, if you do import module1 and import module2 ìn current-project, with xLibrary containing the files module1.py and module2.py), you should include xLibrary in PYTHONPATH just as you did:
PYTHONPATH=.:../xLibrary ./current-project.py

bash$ ln -s ../xLibrary xLibrary

First, it is probably better to use absolute paths in your PYTHONPATH variable.
Second, I don't think you need to add current directory to the path.
Other than that, it would be good to know what it is that doesn't work and what the error message is.
The command line you have there seems to be missing a semicolon
Try these two:
a=12 echo $a
b=12 ;echo $b
...and you'll see the difference.

Apart from the other suggestions, you may consider the virtualenv package. After writing a little setup.py file you can "virtually install" the library and avoid all the PYTHONPATH munging in general.
This is a really good practice and is encouraged by the python community.
Otherwise I prefer the use of sys.path method (by Rakis)