Command-Line Options
Command lines are used to launch Python programs from a system shell prompt. Command-line options intended for Python itself appear before the specification of the program code to be run. Options intended for the code to be run appear after the program specification. Command lines have the following format:
python [option*
] [scriptfilename
| -ccommand
| -mmodule
| - ] [arg*
]
Python Options
-b
Issues warnings for calling
str()
with abytes
orbytearray
object, and comparing abytes
orbytearray
with astr
. Option-bb
issues errors instead.-B
Do not write .pyc or .pyo byte-code files on imports.
-d
Turns on parser debugging output (for developers of the Python core).
-E
Ignores Python environment variables described ahead (such as
PYTHONPATH
).-h
Prints help message and exit.
-i
Enters interactive mode after executing a script. Useful for postmortem debugging.
-O
Optimizes generated byte-code (create and use .pyo byte-code files). Currently yields a minor performance improvement.
-OO
Operates like
-O
, the previous option, but also removes docstrings from byte-code.-s
Do not add the user site directory to the
sys.path
module search path.-S
Do not imply âimport siteâ on initialization.
-u
Forces stdout and stderr to be unbuffered and binary.
-v
Prints a message each time a module is initialized, showing the place from which it is loaded; repeats this flag for more verbose output.
-V
Prints Python version number and exit.
-W
arg
Functions as warning control;
arg
takes the formaction ...
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