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Python Importing package at same level but different directory

python version:3.9.6
I cannot seem to get this to work I know there are a million posts that are the same as this but the solutions never seem to work for me. I've run into this before and always end up just restructuring the folders to include all files in one path which is obviously not ideal. So here I am once again asking you guys for help.
My folder structure is as follows
|project
|my_service
-my_service.py
|tests
- tests.py
I'm trying to get the function get_num_back from my_service.py and import it into tests.py.
I've tried relative imports from ..my_service.my_service import get_num_back this doesn't work because from what I've read I cannot hit the root folder.
I've then tried absolute import from my_service.my_service import get_num_back which is the answer I see works for everyone else but it doesn't seem to work for me. I've then tried from project import my_service as well as from project.my_service import my_service. as far as I understand with my python version I do not need __init__.py but I've also tried it with that as well.
the error
ModuleNotFoundError: No module named 'project'
Please settle this for me once and for all!

Always run py.test from your project directory.
Because from that directory it can actually find my_service.
For more information, read up on relative imports in the language reference documentation.

Cannot import module in same directory and package

I'm using a from . import module statement to do exactly that: import a local module to my script. The script and module reside in the same folder.
# module.py
def foo():
print('Foo!')
# script.py
from . import module
module.foo()
> ImportError: cannot import name 'module'
This should be pretty easy, and doing just import module does work, but as this answer suggests one should, I modified the statements to the former form.
The end goal is to have a package, from which I can use things, but also to have executable scripts inside the package that import other parts of that package. Apparently, after a few days worth of searching and a few questions I still don't quite understand the import and packaging machinery.
These might be the cause:
Import statements are different in 2.7 and 3.x, I'm using 3.6, the question was on 2.7
Relative imports are different inside packages (folder with __init__.py)
The working directory is different or the folders are not in sys.path
Having an __init__ file does not make a difference at least in a fresh project in PyCharm. Also, the working directory is set to the folder of the sources and it is in path.
Have I missed something? Or rather, what's the correct way of achieving the functionality described in the end goal? Any help is greatly appreciated!

Since writing this answer I have realised it is more convenient and better style in my humble opinion to install the package with pip install -e . and use absolute imports. So even within a package writing from package.sub.module import thing. This makes refactoring a lot easier and there's no need to ever manipulate module variables or sys.path.
When running a script directly, Python consideres the name (a special variable, __name__) of that script to be "__main__". In case of an import, the name is set to the name of the module. In the latter case relative imports are fine. But import actually looks at the combination of __name__ and another special variable, __package__, which is None for an executed script, but the path to a module for an imported module, e.g. parent.sub.
The searched variable is... drumroll...
__package__ + '.' + __name__
The secret ingredient is manipulating __package__:
# script.py
__package__ = 'package_name' # or parent.sub.package
from . import module
This lets Python know you are inside a package even though the script is executed directly. However, the top level folder needs to be in sys.path and the package name has to reflect that directory structure.
See this very comprehensive answer on the topic of relative imports.

Importing self-made package

I am testing my own package, but I am struggling to import it. My package file structure is as follows:
(You can also alternatively view my Github repository here)
In PyAdventures is my init.py with the content of
name="pyadventures"
So my question is, when I import it in another python file, how come it doesn't work?
I run:
import pyadventures
But I get the following error:
No module named pyadventures
It'd be great if you could answer my question!
It's important to note that the package is in my Python package directory, not the test one I showed
New discovery! In my PyAdventures folder (the one Python actually uses) the folder only has a few files, not the ones in the screenshot above.
You can install this with pip install pyadventures

Ah, like others remark in comments and answer: The camelcase might be the problem. (Why not name it just all in lower case: pyadventures? - Else users will be as confused as its developer now :D .)
Before, I thought, it might be a problem that you want to use your module without having installed it (locally). And my following answer is for this case (using a not installed package from a local folder):
In the docs you can read:
The variable sys.path is a list of strings that determines the
interpreter’s search path for modules. It is initialized to a default
path taken from the environment variable PYTHONPATH, or from a
built-in default if PYTHONPATH is not set. You can modify it using
standard list operations:
import sys
sys.path.append('/ufs/guido/lib/python')
thus, before import do:
import sys
sys.path.append('/absolute/or/relative/path/to/your/module/pyadventures')
# Now, your module is "visible" for the module loader
import pyadventures
Alternatively, you could just place your pyadventures module folder locally in your working directory where you start python and then just do
import pyadventures
However, it is much easier to manage to keep only one version in one place and refer to this from other places/scripts. (Else you have multiple copies, and have difficulties to track changes on the multiple copies).
As far as I know, your __init__.py doesn't need to contain anything. It works if it is empty. It is there just to mark your directory as a module.

Simple. Even though the package listed on pip is namd pyadventures, in your code the directory is called PyAdventures. So that's what python knows it as. I ran import PyAdventures and it worked fine.

Python import from parent directory and keep flake8 happy

This import works fine, but feels dirty in a few ways. Mainly that it uses a specific number in the slice* to get the parent path, and that it annoys the flake8 linter.
import os
import sys
sys.path.append(os.path.dirname(__file__)[:-5])
from codeHelpers import completion_message
It's in a file system that looks a bit like this:
parent_folder
__init__.py
codeHelpers.py
child_folder
this_file.py
(child_folder is actually called week1, hence the 5 in the slice)
This question is extremely similar to Python import from parent directory, but in that case the discussion focused on whether or not it was good to run tests from the end point. In my case, I have a series of directories that have code that uses helpers that live in the parent.
Context: each directory is a set of weekly exercises, so I'd like to keep them as simple as possible.
Is there a cleaner, more pythonic way to do this import?
#cco solved the number problem, but it's still upsetting the linter.

First since you haven't been specific about which lint error you are getting, I am going to assume it's because you have an import after your sys.path.append.
The cleanest way to do it is with relative or absolute imports.
Using absolute imports:
from parent_path.codeHelpers import completion_message
Using relative imports:
from ..codeHelpers import completion_message
For the simple example listed in the original question this should be all that's required. It's simple, it's pythonic, it's reliable, and it fixes the lint issue.
You may find yourself in a situation where the above does not work for you and sys.path manipulation is still required. A drawback is that your IDE will likely not be able to resolve imports to modules from the new path causing issues such as automatic code completion not working and flagging the imports as errors, even though the code will run properly.
If you find you still need to use sys.path and want to avoid lint errors for this type of situation create a new module and do the sys.path manipulation in it instead. Then make sure that you import your new module before any modules that require the modified sys.path.
For example:
local_imports.py
"""Add a path to sys.path for imports."""
import os
import sys
# Get the current directory
current_path = os.path.dirname(__file__)
# Get the parent directory
parent_path = os.path.dirname(current_path)
# Add the parent directory to sys.path
sys.path.append(parent_path)
Then in the target file:
import local_imports # now using modified sys.path
from codeHelpers import completion_message
The drawback to this is it requires you to include local_imports.py in each child_folder and if the folder structure changes, you would have to modify each one local_imports file.
Where this pattern is really useful is when you need to include external libraries in your package (for example in a libs folder) without requiring the user to install the libs themselves.
If you are using this pattern for a libs folder, you may want to make sure your included libraries are preferred over the installed libraries.
To do so, change
sys.path.append(custom_path)
to
sys.path.insert(1, custom_path)
This will make your custom path the second place the python interpreter will check (the first will still be '' which is the local directory).

You can import from a module a level up in a package by using ... In this_file.py:
from ..codeHelpers import completion_message
Had you wanted to go more levels up just keep adding dots...
While I'm here, just be aware that from ..codeHelpers is a relative import, and you should always use them when importing something in the same package. from codeHelpers is an absolute import, which are ambiguous in Python 2 (should it import from in the package or from the unfortunately named codeHelpers module you have installed on your system?), and in Python 3 actually forbidden as a way to import from within the same module (i.e. they are always absolute). You can read the ancient PEP 328 for an explanation of the difficulties.

It might be easier to use absolute import paths, like the following:
from parent_folder.code_helpers import completion_message
But this would require you to make sure that the PYTHONPATH environment variable is set such that it can see the highest root directory (parent_folder in this case, I think). For instance,
PYTHONPATH=. python parent_directory/child_directory/this_file.py
# here the '.' current directory would contain parent_directory
Make sure to add an __init__.py to the child_directory as well.

You can remove the assumption about the length of the final directory name by applying os.path.dirname twice.
e.g. instead of os.path.dirname(__file__)[:-5], use os.path.dirname(os.path.dirname(__file__))

Either way you have to hack around. If you main goal avoid flakes warnings
add a noqa comment
exec(open("../codeHelpers.py").read(), globals())
you can pass a filename with interpreter option -c (should not bother flakes8)

Python program structure importError

I have this structure of a python project:
RF
\__init__.py
----tools
--------\__init__.py
--------drawtools.py
----examples
--------\__init__.py
--------something.py
All __init__.py are left blank. Now, in "something.py" I type:
from RF.tools.drawtools import *
And I get:
ImportError: No module named RF.tools.drawtools
What's the correct program structure? Do I have to put something in the init files?
I notice that if "something.py" is in the top directory it works. The strange thing is that PyCharm, the IDE I'm using, seems to recognize the import and give me code completion.
I heard something about setting PYTHONPATH but as this project must be shared in a team I'd prefer to keep things as simple as possible (you copy the project from one to one and run it without any annoying importError).

I think that it would work with a relative import, such as
from .. import drawtools