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How do I take functions that I already made to run a program and put them under a class?

I am making a contact list system for a class project and used tkinter to make my gui and sqlite3 for the database. I made a bunch of methods that have basically solved the problem but I noticed the question paper says that the functions need to be in a class. How do I put these functions under a class without messing everything up. I am using python3.

A function in a module is similar to a static method in a class. Without knowing any of your app's specifics:
If you have a function that does what you want
def f():
return 'g'
and you want to encapsulate it in a class
class Q:
pass
just assign it as a static method to that class
Q.f = staticmethod(f)
Whenever you need to use that function you have to call it via the class
>>> Q.f()
g
This is similar to what happens when you import a module that has functions - you import the module and call the functions using the module name (the functions are module attributes) - modulename.func().
I really have no idea how this fits with your need or what any downsides might be.

Does Python import copy all the code into the file

When we import a module in a Python script, does this copy all the required code into the script, or does it just let the script know where to find it?
What happens if we don't use the module then in the code, does it get optimized out somehow, like in C/C++?

None of those things are the case.
An import does two things. First, if the requested module has not previously been loaded, the import loads the module. This mostly boils down to creating a new global scope and executing the module's code in that scope to initialize the module. The new global scope is used as the module's attributes, as well as for global variable lookup for any code in the module.
Second, the import binds whatever names were requested. import whatever binds the whatever name to the whatever module object. import whatever.thing also binds the whatever name to the whatever module object. from whatever import somefunc looks up the somefunc attribute on the whatever module object and binds the somefunc name to whatever the attribute lookup finds.
Unused imports cannot be optimized out, because both the module loading and the name binding have effects that some other code might be relying on.

Python: use of one logger instance across multiple module

As a newbie to python I finally managed to create my own customized logger in a class in an extra module (tools.py). One of the main achievements here is that I can set the name of the logger and with the name also the log file name.
I want to instantiate the logger in main in one module (recalc.py) and from here call a function prepData in another module (getData.py). That function prepData in module getData.py is supposed to use the logger instance I instantiated in recalc.py. prepData is calling other function in the same module that shall use the same logger instance.
I fail to get the grips on how do declare / instantiate the logger since only the in module recalc.py with the main function knows the correct name for the logger.
module tools.py
:
class Logg():
:
.
module recalc.py
import tools
from getData import prepData
:
lg = Logg("recalc", ...) # instantiate the logger
:
result = prepData(...)
.
module getData.py
:
def otherFunc()
lg.debug(...)
:
return X
def prepData(...)
lg.info(...)
:
x = otherFunc(...)
:
return RES
I read a lot about (not really existing) global variables in Python, also Python 3, one class used across multiple modules and others. The config.py solution implies to initiate the global variable in config.py itself. But that doesn't work for me as only the main module knows the logger name.
The workaround I have right now is not acceptable in the long run.
I appreciate any help.

Does Python import instantiate a mystery class?

I thought about this for a while and can't think of a better title, sorry.
I'm new'ish to Python, and (like many other's it seems) I just can't get my head around import.
I think I understand 'modules' and 'packages', classes and attributes and all that. It's one specific behavior I need clarified.
Say I have a file, foo.py. It has one line it:
x = 1
If, in another file, I `import foo", I can reference x. And, wonderfully, in another file I can import foo and now those two files can share x. Leaving classes out of the discussion for simplicity, I believe this is the pythonic way to share attributes between files.
Here's the question: Is is fair to say, when I import foo, that foo.py itself is, (for lack of a better metaphor), secretly instantiated by the interpreter?
I realize if I define a class in a module, it follow traditional rules and only become instantiated if I explicitly do so. But, the python interpreter (via the import statement) instantiating an instance of my module in the global namespace is the only way to explain the attribute sharing behavior.
Is this true? Semi-true? Or am I wandering with the Sleestaks in the Land of the Lost?

When you import a module:
if the module has not been previously imported, the file is parsed in to a module object which is added to sys.modules with a key that is the import path from the pythonpath to your module
that module object (or some member thereof) is aliased in the importing namespace, the alias and object being referenced being determined by the specific form of import you used
So when you import foo, the interpreter checks sys.modules for something registered with the name foo. If it finds it, it provides a label foo in the local namespace for the foo module. If it doesn't, it searches down the pythonpath until it finds a foo module, parses that to a module object, adds that object to sys.modules, and adds a label in the local namespace for that module object.
import foo as foof does the same thing, only the local namespace label created is foof. from foo import x follows the same process up to the point of creating a label and reference in the local namespace, instead providing a label x in the namespace for the attribute x from the foo module. from foo import x as foox just combines the 2 ideas.
With classes, you can actually poke around this whole system by crawling up and down the tree using the __module__ attribute.

The import creates an instance of a "module" object. It is worth knowing that this is created only the first time the module is imported. The following times it is imported you are getting a reference to the original. You can create your own module objects on the fly with a bit of instrospection.
import glob # Import any python module
moduleType = type(glob)
onTheFly = moduleType("OnTheFly", "Docstring for this module")
Although there isn't much benefit to creating these.

Yes, indeed its true. If you execute import foo a module object foo is instatiated and the contents of your file e.g a class bar is added as a member of that object.

Alternative to Passing Global Variables Around to Classes and Functions

I'm new to python, and I've been reading that using global to pass variables to other functions is considered noobie, as well as a bad practice. I would like to move away from using global variables, but I'm not sure what to do instead.
Right now I have a UI I've created in wxPython as its own separate class, and I have another class that loads settings from a .ini file. Since the settings in the UI should match those in the .ini, how do I pass around those values? I could using something like: Settings = Settings() and then define the variables as something like self.settings1, but then I would have to make Settings a global variable to pass it to my UI class (which it wouldn't be if I assign in it main()).
So what is the correct and pythonic way to pass around these variables?
Edit: Here is the code that I'm working with, and I'm trying to get it to work like Alex Martelli's example. The following code is saved in Settings.py:
import ConfigParser
class _Settings():
#property
def enableautodownload(self): return self._enableautodownload
def __init__(self):
self.config = ConfigParser.ConfigParser()
self.config.readfp(open('settings.ini'))
self._enableautodownload=self.config.getboolean('DLSettings', 'enableautodownload')
settings = _Settings()
Whenever I try to refer to Settings.settings.enableautodownload from another file I get: AttributeError: 'module' object has no attribute 'settings'. What am I doing wrong?
Edit 2: Never mind about the issue, I retyped the code and it works now, so it must have been a simple spelling or syntax error.

The alternatives to global variables are many -- mostly:
explicit arguments to functions, classes called to create one of their instance, etc (this is usually the clearest, since it makes the dependency most explicit, when feasible and not too repetitious);
instance variables of an object, when the functions that need access to those values are methods on that same object (that's OK too, and a reasonable way to use OOP);
"accessor functions" that provide the values (or an object which has attributes or properties for the values).
Each of these (esp. the first and third ones) is particularly useful for values whose names must not be re-bound by all and sundry, but only accessed. The really big problem with global is that it provides a "covert communication channel" (not in the cryptographic sense, but in the literal one: apparently separate functions can actually be depending on each other, influencing each other, via global values that are not "obvious" from the functions' signatures -- this makes the code hard to test, debug, maintain, and understand).
For your specific problem, if you never use the global statement, but rather access the settings in a "read-only" way from everywhere (and you can ensure that more fully by making said object's attributes be read-only properties!), then having the "read-only" accesses be performed on a single, made-once-then-not-changed, module-level instance, is not too bad. I.e., in some module foo.py:
class _Settings(object):
#property
def one(self): return self._one
#property
def two(self): return self._two
def __init__(self, one, two):
self._one, self._two = one, two
settings = _Settings(23, 45)
and from everywhere else, import foo then just access foo.settings.one and foo.settings.two as needed. Note that I've named the class with a single leading underscore (just like the two instance attributes that underlie the read-only properties) to suggest that it's not meant to be used from "outside" the module -- only the settings object is supposed to be (there's no enforcement -- but any user violating such requested privacy is most obviously the only party responsible for whatever mayhem may ensue;-).