import distutils.spawn

import os

import sys

def find_executable(executable, path=None):

"""

As distutils.spawn.find_executable, but on Windows, look up

every extension declared in PATHEXT instead of just `.exe`

"""

if sys.platform != 'win32':

return distutils.spawn.find_executable(executable, path)

if path is None:

path = os.environ['PATH']

paths = path.split(os.pathsep)

extensions = os.environ.get('PATHEXT', '.exe').split(os.pathsep)

base, ext = os.path.splitext(executable)

if not os.path.isfile(executable):

for p in paths:

for ext in extensions:

f = os.path.join(p, base + ext)

if os.path.isfile(f):

return f

return None

else:

return executable

def create_environment_dict(overrides):

"""

Create and return a copy of os.environ with the specified overrides

"""

result = os.environ.copy()

result.update(overrides or {})

return result