@@ -273,7 +273,45 @@ field matches the line number, where zero matches all line numbers and
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is thus equivalent to an omitted line number.
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.TP
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.BI " \- X " option
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- Set implementation specific option.
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+ Set implementation specific option. The following options are available:
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+
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+ -X faulthandler: enable faulthandler
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+
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+ -X showrefcount: output the total reference count and number of used
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+ memory blocks when the program finishes or after each statement in the
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+ interactive interpreter. This only works on debug builds
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+
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+ -X tracemalloc: start tracing Python memory allocations using the
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+ tracemalloc module. By default, only the most recent frame is stored in a
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+ traceback of a trace. Use -X tracemalloc=NFRAME to start tracing with a
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+ traceback limit of NFRAME frames
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+
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+ -X showalloccount: output the total count of allocated objects for each
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+ type when the program finishes. This only works when Python was built with
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+ COUNT_ALLOCS defined
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+
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+ -X importtime: show how long each import takes. It shows module name,
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+ cumulative time (including nested imports) and self time (excluding
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+ nested imports). Note that its output may be broken in multi-threaded
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+ application. Typical usage is python3 -X importtime -c 'import asyncio'
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+
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+ -X dev: enable CPython’s “development mode”, introducing additional runtime
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+ checks which are too expensive to be enabled by default. It will not be
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+ more verbose than the default if the code is correct: new warnings are
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+ only emitted when an issue is detected. Effect of the developer mode:
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+ * Add default warning filter, as -W default
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+ * Install debug hooks on memory allocators: see the PyMem_SetupDebugHooks() C function
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+ * Enable the faulthandler module to dump the Python traceback on a crash
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+ * Enable asyncio debug mode
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+ * Set the dev_mode attribute of sys.flags to True
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+ * io.IOBase destructor logs close() exceptions
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+
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+ -X utf8: enable UTF-8 mode for operating system interfaces, overriding the default
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+ locale-aware mode. -X utf8=0 explicitly disables UTF-8 mode (even when it would
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+ otherwise activate automatically). See PYTHONUTF8 for more details
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+
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+ -X pycache_prefix=PATH: enable writing .pyc files to a parallel tree rooted at the
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+ given directory instead of to the code tree.
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.TP
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.B \- x
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Skip the first line of the source. This is intended for a DOS
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