datetime escapes the sandbox. The Windows build is all set. I leave it

to others to argue about how to build it on other platforms (on Windows
it's in its own DLL).

Include/datetime.h

@@ -0,0 +1,125 @@
+/*  datetime.h
+ */
+
+#ifndef DATETIME_H
+#define DATETIME_H
+
+/* Fields are packed into successive bytes, each viewed as unsigned and
+ * big-endian, unless otherwise noted:
+ *
+ * byte offset
+ *  0 		year     2 bytes, 1-9999
+ *  2		month    1 byte, 1-12
+ *  3 		day      1 byte, 1-31
+ *  4		hour     1 byte, 0-23
+ *  5 		minute   1 byte, 0-59
+ *  6 		second   1 byte, 0-59
+ *  7 		usecond  3 bytes, 0-999999
+ * 10
+ */
+
+/* # of bytes for year, month, and day. */
+#define _PyDateTime_DATE_DATASIZE 4
+
+/* # of bytes for hour, minute, second, and usecond. */
+#define _PyDateTime_TIME_DATASIZE 6
+
+/* # of bytes for year, month, day, hour, minute, second, and usecond. */
+#define _PyDateTime_DATETIME_DATASIZE 10
+
+typedef struct
+{
+	PyObject_HEAD
+	long hashcode;
+	unsigned char data[_PyDateTime_DATE_DATASIZE];
+} PyDateTime_Date;
+
+typedef struct
+{
+	PyObject_HEAD
+	long hashcode;
+	unsigned char data[_PyDateTime_DATETIME_DATASIZE];
+} PyDateTime_DateTime;
+
+typedef struct
+{
+	PyObject_HEAD
+	long hashcode;
+	unsigned char data[_PyDateTime_DATETIME_DATASIZE];
+	PyObject *tzinfo;
+} PyDateTime_DateTimeTZ;
+
+typedef struct
+{
+	PyObject_HEAD
+	long hashcode;
+	unsigned char data[_PyDateTime_TIME_DATASIZE];
+} PyDateTime_Time;
+
+typedef struct
+{
+	PyObject_HEAD
+	long hashcode;
+	unsigned char data[_PyDateTime_TIME_DATASIZE];
+	PyObject *tzinfo;
+} PyDateTime_TimeTZ;
+
+typedef struct
+{
+	PyObject_HEAD
+	long hashcode;		/* -1 when unknown */
+	int days;		/* -MAX_DELTA_DAYS <= days <= MAX_DELTA_DAYS */
+	int seconds;		/* 0 <= seconds < 24*3600 is invariant */
+	int microseconds;	/* 0 <= microseconds < 1000000 is invariant */
+} PyDateTime_Delta;
+
+typedef struct
+{
+	PyObject_HEAD		/* a pure abstract base clase */
+} PyDateTime_TZInfo;
+
+/* Apply for date, datetime, and datetimetz instances. */
+#define PyDateTime_GET_YEAR(o)     ((((PyDateTime_Date*)o)->data[0] << 8) | \
+                                     ((PyDateTime_Date*)o)->data[1])
+#define PyDateTime_GET_MONTH(o)    (((PyDateTime_Date*)o)->data[2])
+#define PyDateTime_GET_DAY(o)      (((PyDateTime_Date*)o)->data[3])
+
+#define PyDateTime_DATE_GET_HOUR(o)        (((PyDateTime_DateTime*)o)->data[4])
+#define PyDateTime_DATE_GET_MINUTE(o)      (((PyDateTime_DateTime*)o)->data[5])
+#define PyDateTime_DATE_GET_SECOND(o)      (((PyDateTime_DateTime*)o)->data[6])
+#define PyDateTime_DATE_GET_MICROSECOND(o) 		\
+	((((PyDateTime_DateTime*)o)->data[7] << 16) |	\
+         (((PyDateTime_DateTime*)o)->data[8] << 8)  |	\
+          ((PyDateTime_DateTime*)o)->data[9])
+
+/* Apply for time and timetz instances. */
+#define PyDateTime_TIME_GET_HOUR(o)        (((PyDateTime_Time*)o)->data[0])
+#define PyDateTime_TIME_GET_MINUTE(o)      (((PyDateTime_Time*)o)->data[1])
+#define PyDateTime_TIME_GET_SECOND(o)      (((PyDateTime_Time*)o)->data[2])
+#define PyDateTime_TIME_GET_MICROSECOND(o) 		\
+	((((PyDateTime_Time*)o)->data[3] << 16) |	\
+         (((PyDateTime_Time*)o)->data[4] << 8)  |	\
+          ((PyDateTime_Time*)o)->data[5])
+
+#define PyDate_Check(op) PyObject_TypeCheck(op, &PyDateTime_DateType)
+#define PyDate_CheckExact(op) ((op)->ob_type == &PyDateTime_DateType)
+
+#define PyDateTime_Check(op) PyObject_TypeCheck(op, &PyDateTime_DateTimeType)
+#define PyDateTime_CheckExact(op) ((op)->ob_type == &PyDateTime_DateTimeType)
+
+#define PyDateTimeTZ_Check(op) PyObject_TypeCheck(op, &PyDateTime_DateTimeTZType)
+#define PyDateTimeTZ_CheckExact(op) ((op)->ob_type == &PyDateTime_DateTimeTZType)
+
+#define PyTime_Check(op) PyObject_TypeCheck(op, &PyDateTime_TimeType)
+#define PyTime_CheckExact(op) ((op)->ob_type == &PyDateTime_TimeType)
+
+#define PyTimeTZ_Check(op) PyObject_TypeCheck(op, &PyDateTime_TimeTZType)
+#define PyTimeTZ_CheckExact(op) ((op)->ob_type == &PyDateTime_TimeTZType)
+
+#define PyDelta_Check(op) PyObject_TypeCheck(op, &PyDateTime_DeltaType)
+#define PyDelta_CheckExact(op) ((op)->ob_type == &PyDateTime_DeltaType)
+
+#define PyTZInfo_Check(op) PyObject_TypeCheck(op, &PyDateTime_TZInfoType)
+#define PyTZInfo_CheckExact(op) ((op)->ob_type == &PyDateTime_TZInfoType)
+
+#endif