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Call a Python 2.7 module in Python 3.2

I have a GUI program that I have developed in Python 3.2 to extract various geospatial data products. I need to call a module I have developed in Python 2.7.
I am looking for a way to be able to call the Python 2.7 code using a Python 2.7 interpreter inside of Python 3.2 program. I cannot port the 2.7 to Python 3.2 as it uses a Python version installed with ESRI ArcMap and relies on the arcpy module which is not available for Python 3. My only idea right now would be to use subprocess to call the module as a batch process however this is a bit messy and I would prefer the two programs had some relationship.
Thank you in advance.

You could spawn the python 2.7 process as a server handling RPC requests from your GUI running on 3.2. That will work either over the network, or local pipes, or shared memory, or your system's message bus, or many other ways. You just need to translate your library's API into some kind of serialised messages.
Let's say your library has a function: (super simplified example)
def add(a, b):
return a+b
You'd wrap this in some server, let's say a flask app, which does:
#app.route("/add", methods=["POST"])
def handle_add():
data = request.get_json()
ret = your_lib.add(data['a'], data['b'])
return jsonify(ret)
and on the client side, send and unpack the values using something like requests
You could even make it fairly transparent by implementing a translator module with methods named the same as the library itself and doing import your_http_wrapper as your_library_name.
The trick now is to make sure all your parameters can be serialised and that you can realistically send all the arguments/return values in a reasonable time on each call. Also, you lose the ability to change the contents of the variables you pass to the wrapper, because the server will modify only the local copy (unless you implement serialising all those modifications as well)

Try using subprocess.check_output(['C:\\python27\\python.exe', 'yourModule.py'])
If you want to call a specific function within the 27 file, you can use more system arguments. The call would look like:
subprocess.check_output(['C:\\python27\\python.exe', 'yourModule.py', 'funcName'])
And in the 27 file you can add:
import sys
if __name__=='__main__':
if 'funcName' in sys.argv:
funcName()
else:
#... execute normally

Somewhat late but in case someone stumbles over this thread:
I've written a module that transparently runs parts of a program in other python interpreters. Basically it provides decorators and base classes that replace functions and objects with proxies that interface with other interpreters.
It's intended for compatibility, e.g. running python2 only code in python3, or accessing C modules from pypy.
In the following example, the loop runs 4x as fast via using pypy as it would with plain python.
#!/usr/local/bin/python
from cpy2py import TwinMaster, twinfunction
import sys
import time
import math
# loops in PyPy
#twinfunction('pypy')
def prime_sieve(max_val):
start_time = time.time()
primes = [1] * 2 + [0] * (max_val - 1)
for value, factors in enumerate(primes):
if factors == 0:
for multiple in xrange(value*value, max_val + 1, value):
primes[multiple] += 1
return {'xy': [
[primes[idx] == 0 for idx in range(minidx, minidx + int(math.sqrt(max_val)))]
for minidx in range(0, max_val, int(math.sqrt(max_val)))
], 'info': '%s in %.1fs' % (sys.executable, time.time() - start_time)}
# matplotlib in CPython
#twinfunction('python')
def draw(xy, info='<None>'):
from matplotlib import pyplot
pyplot.copper()
pyplot.matshow(xy)
pyplot.xlabel(info, color="red")
pyplot.show()
if __name__ == '__main__':
twins = [TwinMaster('python'), TwinMaster('pypy')]
for twin in twins:
twin.start()
data = prime_sieve(int(1E6))
draw(**data)

Call Python code from an existing project written in Swift

I need a way to call Python code from Swift on an Apple platform. A library would be ideal. I've done a considerable amount of Google searching, and the closest material I found is for Objective-C.

In swift 5 you can try PythonKit framework.
Here's example of the usage:
import PythonKit
let sys = try Python.import("sys")
print("Python \(sys.version_info.major).\(sys.version_info.minor)")
print("Python Version: \(sys.version)")
print("Python Encoding: \(sys.getdefaultencoding().upper())")

I found this excellent and up to date gist that walks you through a complete solution: https://github.com/ndevenish/Site-ndevenish/blob/master/_posts/2017-04-11-using-python-with-swift-3.markdown
If you can get away with just using NSTask to launch a Python process, that's a pretty good option too.

In Swift 4.2 there was an approved feature to allow dynamic languages to be ported directly into swift
https://github.com/apple/swift-evolution/blob/master/proposals/0195-dynamic-member-lookup.md
Will look similar to:
// import pickle
let pickle = Python.import("pickle")
// file = open(filename)
let file = Python.open(filename)
// blob = file.read()
let blob = file.read()
// result = pickle.loads(blob)
let result = pickle.loads(blob)

If anyone is ever interested in calling python from swift, here is some helpful material I found:
U the python framework - https://developer.apple.com/library/ios/technotes/tn2328/_index.html
PyObjC (a little more challenging) -
Cobbal - https://github.com/cobbal/python-for-iphone
Python docs (you would need to make C-Swift bridge)
Most of it is for Objective-c, but if you need to use swift you can easily just create an ObjC-Swift bridge (super-super easy) - Lookup the apple docs

Python - How to get the start/base address of a process?

How do I get the start/base address of a process? Per example Solitaire.exe (solitaire.exe+BAFA8)
#-*- coding: utf-8 -*-
import ctypes, win32ui, win32process
PROCESS_ALL_ACCESS = 0x1F0FFF
HWND = win32ui.FindWindow(None,u"Solitär").GetSafeHwnd()
PID = win32process.GetWindowThreadProcessId(HWND)[1]
PROCESS = ctypes.windll.kernel32.OpenProcess(PROCESS_ALL_ACCESS,False,PID)
print PID, HWND,PROCESS
I would like to calculate a memory address and for this way I need the base address of solitaire.exe.
Here's a picture of what I mean:

I think the handle returned by GetModuleHandle is actually the base address of the given module. You get the handle of the exe by passing NULL.

Install pydbg
Source: https://github.com/OpenRCE/pydbg
Unofficial binaries here: http://www.lfd.uci.edu/~gohlke/pythonlibs/#pydbg
from pydbg import *
from pydbg.defines import *
import struct
dbg = pydbg()
path_exe = "C:\\windows\\system32\\calc.exe"
dbg.load(path_exe, "-u amir")
dbg.debug_event_loop()
parameter_addr = dbg.context.Esp #(+ 0x8)
print 'ESP (address) ',parameter_addr
#attach not working under Win7 for me
#pid = raw_input("Enter PID:")
#print 'PID entered %i'%int(pid)
#dbg.attach(int(pid)) #attaching to running process not working
You might want to have a look at PaiMei, although it's not very active right now https://github.com/OpenRCE/paimei
I couldn't get attach() to work and used load instead. Pydbg has loads of functionality, such as read_proccess_memory, write_process_memory etc.
Note that you can't randomly change memory, because an operating system protects memory of other processes from your process (protected mode). Before the x86 processors there were some which allowed all processors to run in real mode, i.e. the full access of memory for every programm. Non-malicious software usually (always?) doesn't read/write other processes' memory.

The HMDOULE value of GetModuleHandle is the base address of the loaded module and is probably the address you need to compute the offset.
If not, that address is the start of the header of the module (DLL/EXE), which can be displayed with the dumpbin utility that comes with Visual Studio or you can interpret it yourself using the Microsoft PE and COFF Specification to determine the AddressOfEntryPoint and BaseOfCode as offsets from the base address. If the base address of the module isn't what you need, one of these two is another option.
Example:
>>> BaseAddress = win32api.GetModuleHandle(None) + 0xBAFA8
>>> print '{:08X}'.format(BaseAddress)
1D0BAFA8
If The AddressOfEntryPoint or BaseOfCode is needed, you'll have to use ctypes to call ReadProcessMemory following the PE specification to locate the offsets, or just use dumpbin /headers solitaire.exe to learn the offsets.

You can use frida to easy do that.
It is very useful to make hack and do some memory operation just like make address offset, read memory, write something to special memory etc...
https://github.com/frida/frida
2021.08.01 update:
Thanks for #Simas Joneliunas reminding
There some step using frida(windows):
Install frida by pip
pip install frida-tools # CLI tools
pip install frida # Python bindings
Using frida api
session = frida.attach(processName)
script = session.create_script("""yourScript""")
script.load()
sys.stdin.read() #make program always alive
session.detach()
Edit your scrip(using JavaScrip)
var baseAddr = Module.findBaseAddress('solitaire.exe');
var firstPointer = baseAddr.add(0xBAFA8).readPointer();
var secondPointer = firstPointer.add(0x50).readPointer();
var thirdPointer = secondPointer.add(0x14).readPointer();
#if your target pointer points to a Ansi String, you can use #thirdPointer.readAnsiString() to read
The official site https://frida.re/

Available disk space on an SMB share, via Python

Does anyone know a way to get the amount of space available on a Windows (Samba) share via Python 2.6 with its standard library? (also running on Windows)
e.g.
>>> os.free_space("\\myshare\folder") # return free disk space, in bytes
1234567890

If PyWin32 is available:
free, total, totalfree = win32file.GetDiskFreeSpaceEx(r'\\server\share')
Where free is a amount of free space available to the current user, and totalfree is amount of free space total. Relevant documentation: PyWin32 docs, MSDN.
If PyWin32 is not guaranteed to be available, then for Python 2.5 and higher there is ctypes module in stdlib. Same function, using ctypes:
import sys
from ctypes import *
c_ulonglong_p = POINTER(c_ulonglong)
_GetDiskFreeSpace = windll.kernel32.GetDiskFreeSpaceExW
_GetDiskFreeSpace.argtypes = [c_wchar_p, c_ulonglong_p, c_ulonglong_p, c_ulonglong_p]
def GetDiskFreeSpace(path):
if not isinstance(path, unicode):
path = path.decode('mbcs') # this is windows only code
free, total, totalfree = c_ulonglong(0), c_ulonglong(0), c_ulonglong(0)
if not _GetDiskFreeSpace(path, pointer(free), pointer(total), pointer(totalfree)):
raise WindowsError
return free.value, total.value, totalfree.value
Could probably be done better but I'm not really familiar with ctypes.

The standard library has the os.statvfs() function, but unfortunately it's only available on Unix-like platforms.
In case there is some cygwin-python maybe it would work there?

Finding the Current Active Window in Mac OS X using Python

Is there a way to find the application name of the current active window at a given time on Mac OS X using Python?

This should work:
#!/usr/bin/python
from AppKit import NSWorkspace
activeAppName = NSWorkspace.sharedWorkspace().activeApplication()['NSApplicationName']
print activeAppName
Only works on Leopard, or on Tiger if you have PyObjC installed and happen to point at the right python binary in line one (not the case if you've installed universal MacPython, which you'd probably want to do on Tiger). But Peter's answer with the Carbon way of doing this will probably be quite a bit faster, since importing anything from AppKit in Python takes a while, or more accurately, importing something from AppKit for the first time in a Python process takes a while.
If you need this inside a PyObjC app, what I describe will work great and fast, since you only experience the lag of importing AppKit once. If you need this to work as a command-line tool, you'll notice the performance hit. If that's relevant to you, you're probably better off building a 10 line Foundation command line tool in Xcode using Peter's code as a starting point.

The method in the accepted answer was deprecated in OS X 10.7+. The current recommended version would be the following:
from AppKit import NSWorkspace
active_app_name = NSWorkspace.sharedWorkspace().frontmostApplication().localizedName()
print(active_app_name)

First off, do you want the window or the application name? This isn't Windows—an application process on Mac OS X can have multiple windows. (Furthermore, this has also been true of Windows for a few years now, although I have no idea what the API looks like for that.)
Second, Carbon or Cocoa?
To get the active window in Cocoa:
window = NSApp.mainWindow()
To get the name of your process in Cocoa:
appName = NSProcessInfo.processInfo().processName()
Edit: Oh, I think I know what you want. The name of the frontmost process, right?
I don't think there's a way to do it in Cocoa, but here's how to do it in Carbon in C:
ProcessSerialNumber psn = { 0L, 0L };
OSStatus err = GetFrontProcess(&psn);
/*error check*/
CFStringRef processName = NULL;
err = CopyProcessName(&psn, &processName);
/*error check*/
Remember to CFRelease(processName) when you're done with it.
I'm not sure what that will look like in Python, or if it's even possible. Python doesn't have pointers, which makes that tricky.
I know PyObjC would translate the latter argument to CopyProcessName into err, processName = CopyProcessName(…), but the Carbon bindings don't rely on PyObjC (they're part of core Python 2), and I'm not sure what you do about the PSN either way.

I needed the current frontmost application in a Python script that arranges the windows nicely on my screen (see move_window).
Of course, the complete credit goes to Peter! But here is the complete program:
#include <Carbon/Carbon.h>
int main(int, char) {
ProcessSerialNumber psn = { 0L, 0L };
OSStatus err = GetFrontProcess(&psn);
CFStringRef processName = NULL;
err = CopyProcessName(&psn, &processName);
printf("%s\n", CFStringGetCStringPtr(processName, NULL));
CFRelease(processName);
}
Build with gcc -framework Carbon filename.c