mirror of
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194 lines
7.2 KiB
C
194 lines
7.2 KiB
C
#ifndef Py_PYMACRO_H
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#define Py_PYMACRO_H
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// gh-91782: On FreeBSD 12, if the _POSIX_C_SOURCE and _XOPEN_SOURCE macros are
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// defined, <sys/cdefs.h> disables C11 support and <assert.h> does not define
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// the static_assert() macro.
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// https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=255290
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//
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// macOS <= 10.10 doesn't define static_assert in assert.h at all despite
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// having C11 compiler support.
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//
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// static_assert is defined in glibc from version 2.16. Compiler support for
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// the C11 _Static_assert keyword is in gcc >= 4.6.
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//
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// MSVC makes static_assert a keyword in C11-17, contrary to the standards.
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//
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// In C++11 and C2x, static_assert is a keyword, redefining is undefined
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// behaviour. So only define if building as C, not C++ (if __cplusplus is
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// not defined), and only for C11-17.
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#if !defined(static_assert) && (defined(__GNUC__) || defined(__clang__)) \
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&& !defined(__cplusplus) && defined(__STDC_VERSION__) \
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&& __STDC_VERSION__ >= 201112L && __STDC_VERSION__ <= 201710L
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# define static_assert _Static_assert
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#endif
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/* Minimum value between x and y */
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#define Py_MIN(x, y) (((x) > (y)) ? (y) : (x))
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/* Maximum value between x and y */
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#define Py_MAX(x, y) (((x) > (y)) ? (x) : (y))
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/* Absolute value of the number x */
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#define Py_ABS(x) ((x) < 0 ? -(x) : (x))
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#define _Py_XSTRINGIFY(x) #x
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/* Convert the argument to a string. For example, Py_STRINGIFY(123) is replaced
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with "123" by the preprocessor. Defines are also replaced by their value.
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For example Py_STRINGIFY(__LINE__) is replaced by the line number, not
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by "__LINE__". */
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#define Py_STRINGIFY(x) _Py_XSTRINGIFY(x)
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/* Get the size of a structure member in bytes */
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#define Py_MEMBER_SIZE(type, member) sizeof(((type *)0)->member)
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/* Argument must be a char or an int in [-128, 127] or [0, 255]. */
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#define Py_CHARMASK(c) ((unsigned char)((c) & 0xff))
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#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L \
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&& !defined(__cplusplus) && !defined(_MSC_VER))
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# define Py_BUILD_ASSERT_EXPR(cond) \
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((void)sizeof(struct { int dummy; _Static_assert(cond, #cond); }), \
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0)
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#else
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/* Assert a build-time dependency, as an expression.
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*
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* Your compile will fail if the condition isn't true, or can't be evaluated
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* by the compiler. This can be used in an expression: its value is 0.
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*
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* Example:
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*
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* #define foo_to_char(foo) \
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* ((char *)(foo) \
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* + Py_BUILD_ASSERT_EXPR(offsetof(struct foo, string) == 0))
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*
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* Written by Rusty Russell, public domain, http://ccodearchive.net/
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*/
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# define Py_BUILD_ASSERT_EXPR(cond) \
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(sizeof(char [1 - 2*!(cond)]) - 1)
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#endif
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#if ((defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L) \
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|| (defined(__cplusplus) && __cplusplus >= 201103L))
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// Use static_assert() on C11 and newer
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# define Py_BUILD_ASSERT(cond) \
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do { \
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static_assert((cond), #cond); \
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} while (0)
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#else
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# define Py_BUILD_ASSERT(cond) \
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do { \
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(void)Py_BUILD_ASSERT_EXPR(cond); \
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} while(0)
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#endif
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/* Get the number of elements in a visible array
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This does not work on pointers, or arrays declared as [], or function
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parameters. With correct compiler support, such usage will cause a build
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error (see Py_BUILD_ASSERT_EXPR).
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Written by Rusty Russell, public domain, http://ccodearchive.net/
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Requires at GCC 3.1+ */
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#if (defined(__GNUC__) && !defined(__STRICT_ANSI__) && \
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(((__GNUC__ == 3) && (__GNUC_MINOR__ >= 1)) || (__GNUC__ >= 4)))
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/* Two gcc extensions.
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&a[0] degrades to a pointer: a different type from an array */
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#define Py_ARRAY_LENGTH(array) \
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(sizeof(array) / sizeof((array)[0]) \
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+ Py_BUILD_ASSERT_EXPR(!__builtin_types_compatible_p(typeof(array), \
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typeof(&(array)[0]))))
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#else
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#define Py_ARRAY_LENGTH(array) \
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(sizeof(array) / sizeof((array)[0]))
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#endif
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/* Define macros for inline documentation. */
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#define PyDoc_VAR(name) static const char name[]
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#define PyDoc_STRVAR(name,str) PyDoc_VAR(name) = PyDoc_STR(str)
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#ifdef WITH_DOC_STRINGS
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#define PyDoc_STR(str) str
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#else
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#define PyDoc_STR(str) ""
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#endif
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/* Below "a" is a power of 2. */
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/* Round down size "n" to be a multiple of "a". */
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#define _Py_SIZE_ROUND_DOWN(n, a) ((size_t)(n) & ~(size_t)((a) - 1))
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/* Round up size "n" to be a multiple of "a". */
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#define _Py_SIZE_ROUND_UP(n, a) (((size_t)(n) + \
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(size_t)((a) - 1)) & ~(size_t)((a) - 1))
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/* Round pointer "p" down to the closest "a"-aligned address <= "p". */
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#define _Py_ALIGN_DOWN(p, a) ((void *)((uintptr_t)(p) & ~(uintptr_t)((a) - 1)))
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/* Round pointer "p" up to the closest "a"-aligned address >= "p". */
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#define _Py_ALIGN_UP(p, a) ((void *)(((uintptr_t)(p) + \
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(uintptr_t)((a) - 1)) & ~(uintptr_t)((a) - 1)))
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/* Check if pointer "p" is aligned to "a"-bytes boundary. */
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#define _Py_IS_ALIGNED(p, a) (!((uintptr_t)(p) & (uintptr_t)((a) - 1)))
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/* Use this for unused arguments in a function definition to silence compiler
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* warnings. Example:
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*
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* int func(int a, int Py_UNUSED(b)) { return a; }
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*/
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#if defined(__GNUC__) || defined(__clang__)
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# define Py_UNUSED(name) _unused_ ## name __attribute__((unused))
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#elif defined(_MSC_VER)
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// Disable warning C4100: unreferenced formal parameter,
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// declare the parameter,
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// restore old compiler warnings.
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# define Py_UNUSED(name) \
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__pragma(warning(push)) \
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__pragma(warning(suppress: 4100)) \
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_unused_ ## name \
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__pragma(warning(pop))
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#else
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# define Py_UNUSED(name) _unused_ ## name
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#endif
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#if defined(RANDALL_WAS_HERE)
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# define Py_UNREACHABLE() \
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Py_FatalError( \
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"If you're seeing this, the code is in what I thought was\n" \
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"an unreachable state.\n\n" \
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"I could give you advice for what to do, but honestly, why\n" \
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"should you trust me? I clearly screwed this up. I'm writing\n" \
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"a message that should never appear, yet I know it will\n" \
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"probably appear someday.\n\n" \
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"On a deep level, I know I'm not up to this task.\n" \
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"I'm so sorry.\n" \
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"https://xkcd.com/2200")
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#elif defined(Py_DEBUG)
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# define Py_UNREACHABLE() \
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Py_FatalError( \
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"We've reached an unreachable state. Anything is possible.\n" \
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"The limits were in our heads all along. Follow your dreams.\n" \
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"https://xkcd.com/2200")
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#elif defined(__GNUC__) && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 5))
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# define Py_UNREACHABLE() __builtin_unreachable()
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#elif defined(__clang__) || defined(__INTEL_COMPILER)
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# define Py_UNREACHABLE() __builtin_unreachable()
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#elif defined(_MSC_VER)
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# define Py_UNREACHABLE() __assume(0)
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#else
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# define Py_UNREACHABLE() \
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Py_FatalError("Unreachable C code path reached")
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#endif
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#define _Py_CONTAINER_OF(ptr, type, member) \
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(type*)((char*)ptr - offsetof(type, member))
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// Prevent using an expression as a l-value.
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// For example, "int x; _Py_RVALUE(x) = 1;" fails with a compiler error.
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#define _Py_RVALUE(EXPR) ((void)0, (EXPR))
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// Return non-zero if the type is signed, return zero if it's unsigned.
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// Use "<= 0" rather than "< 0" to prevent the compiler warning:
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// "comparison of unsigned expression in '< 0' is always false".
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#define _Py_IS_TYPE_SIGNED(type) ((type)(-1) <= 0)
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#endif /* Py_PYMACRO_H */
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