· coding · 1 min read
Environment Variables in Python
Python code reference and cookbook.

Q: Difference between os.getenv
and os.environ
When the environment variable has been set, there is no difference.
$ python -m timeit -s 'import os' 'os.environ.get("ENV_VAR_FOO")'
200000 loops, best of 5: 1.65 usec per loop
$ python -m timeit -s 'import os' 'os.getenv("ENV_VAR_FOO")'
200000 loops, best of 5: 1.83 usec per loop
os.environ
is of the built-in type _Environ
, which is a MutableMapping
.
from _collections_abc import MutableMapping
class _Environ(MutableMapping):
...
In other words, os.environ
is a dictionary. Its keys-value pairs are formed by your environment variables.
import dotenv # poetry add python-dotenv
dotenv.load_dotenv()