typedef struct {PyObject_HEADPyObject *func_code;  //编译后的PyCodeObject对象PyObject *func_globals; //函数运行时的global名字空间PyObject *func_defaults;  //默认参数（tupple或NULL）PyObject *func_closure;    //NULL or a tuple of cell objects，用于实现closure(闭包)PyObject *func_doc;     //函数的文档（PyStringObject）PyObject *func_name;   //函数名称，函数的__name__属性，（PyStringObject）PyObject *func_dict;   //函数的__dict__属性（PyDictObject或NULL）PyObject *func_weakreflist; PyObject *func_module;  //函数的__module__，可以是任何对象
} PyFunctionObject;

# cat demo.py
def f():print("Function")f()# python2.5
……
>>> source = open("demo.py").read()
>>> co = compile(source, "demo.py", "exec")
>>> import dis
>>> dis.dis(co)1           0 LOAD_CONST               0 (<code object f at 0x7fd9831c3648, file "demo.py", line 1>)3 MAKE_FUNCTION            06 STORE_NAME               0 (f)5           9 LOAD_NAME                0 (f)12 CALL_FUNCTION            015 POP_TOP             16 LOAD_CONST               1 (None)19 RETURN_VALUE
>>> from demo import f
Function
>>> dis.dis(f)2           0 LOAD_CONST               1 ('Function')3 PRINT_ITEM          4 PRINT_NEWLINE       5 LOAD_CONST               0 (None)8 RETURN_VALUE

case MAKE_FUNCTION:v = POP(); //获得与函数f对应的PyCodeObjectx = PyFunction_New(v, f->f_globals);Py_DECREF(v);//处理函数参数的默认值if (x != NULL && oparg > 0){v = PyTuple_New(oparg);if (v == NULL){Py_DECREF(x);x = NULL;break;}while (--oparg >= 0){w = POP();PyTuple_SET_ITEM(v, oparg, w);}err = PyFunction_SetDefaults(x, v);Py_DECREF(v);}PUSH(x);break;

PyObject * PyFunction_New(PyObject *code, PyObject *globals)
{//[1]：申请PyFunctionObject对象所需的内存空间PyFunctionObject *op = PyObject_GC_New(PyFunctionObject, &PyFunction_Type);static PyObject *__name__ = 0;if (op != NULL) {……//设置PyCodeObject对象op->func_code = code;//设置global名字空间op->func_globals = globals;//设置函数名op->func_name = ((PyCodeObject *)code)->co_name;Py_INCREF(op->func_name);op->func_defaults = NULL; /* No default arguments */op->func_closure = NULL;//函数中的常量对象表consts = ((PyCodeObject *)code)->co_consts;//函数文档if (PyTuple_Size(consts) >= 1) {doc = PyTuple_GetItem(consts, 0);if (!PyString_Check(doc) && !PyUnicode_Check(doc))doc = Py_None;}elsedoc = Py_None;……}elsereturn NULL;_PyObject_GC_TRACK(op);return (PyObject *)op;
}

case CALL_FUNCTION:{PyObject **sp;PCALL(PCALL_ALL);sp = stack_pointer;x = call_function(&sp, oparg);stack_pointer = sp;PUSH(x);if (x != NULL)continue;break;}

static PyObject * call_function(PyObject ***pp_stack, int oparg)
{//[1]：处理函数参数信息int na = oparg & 0xff;int nk = (oparg >> 8) & 0xff;int n = na + 2 * nk;//[2]：获得PyFunctionObject对象PyObject **pfunc = (*pp_stack) - n - 1;PyObject *func = *pfunc;PyObject *x, *w;if (PyCFunction_Check(func) && nk == 0){……}else{if (PyMethod_Check(func) && PyMethod_GET_SELF(func) != NULL){……}elsePy_INCREF(func);READ_TIMESTAMP(*pintr0);//[3]：对PyFunctionObject对象进行调用if (PyFunction_Check(func))x = fast_function(func, pp_stack, n, na, nk);elsex = do_call(func, pp_stack, na, nk);……}……return x;
}

static PyObject * fast_function(PyObject *func, PyObject ***pp_stack, int n, int na, int nk)
{PyCodeObject *co = (PyCodeObject *)PyFunction_GET_CODE(func);PyObject *globals = PyFunction_GET_GLOBALS(func);PyObject *argdefs = PyFunction_GET_DEFAULTS(func);PyObject **d = NULL;int nd = 0;……//[1]：一般函数的快速通道if (argdefs == NULL && co->co_argcount == n && nk == 0 &&co->co_flags == (CO_OPTIMIZED | CO_NEWLOCALS | CO_NOFREE)){PyFrameObject *f;PyObject *retval = NULL;PyThreadState *tstate = PyThreadState_GET();PyObject **fastlocals, **stack;int i;……f = PyFrame_New(tstate, co, globals, NULL);……//再次进入Python虚拟机retval = PyEval_EvalFrameEx(f, 0);……return retval;}if (argdefs != NULL){d = &PyTuple_GET_ITEM(argdefs, 0);nd = ((PyTupleObject *)argdefs)->ob_size;}//PyEval_EvalCodeEx的实现中，依然会调用PyEval_EvalFrameExreturn PyEval_EvalCodeEx(co, globals,(PyObject *)NULL, (*pp_stack) - n, na,(*pp_stack) - 2 * nk, nk, d, nd,PyFunction_GET_CLOSURE(func));
}