diff --git a/Lib/bisect.py b/Lib/bisect.py
@@ -11,7 +11,7 @@ def insort_right(a, x, lo=0, hi=None):
 
     if lo < 0:
         raise ValueError('lo must be non-negative')
-    if hi is None:
+    if hi is None or hi == -1:
         hi = len(a)
     while lo < hi:
         mid = (lo+hi)//2
@@ -32,7 +32,7 @@ def bisect_right(a, x, lo=0, hi=None):
 
     if lo < 0:
         raise ValueError('lo must be non-negative')
-    if hi is None:
+    if hi is None or hi == -1:
         hi = len(a)
     while lo < hi:
         mid = (lo+hi)//2
@@ -51,7 +51,7 @@ def insort_left(a, x, lo=0, hi=None):
 
     if lo < 0:
         raise ValueError('lo must be non-negative')
-    if hi is None:
+    if hi is None or hi == -1:
         hi = len(a)
     while lo < hi:
         mid = (lo+hi)//2
@@ -73,7 +73,7 @@ def bisect_left(a, x, lo=0, hi=None):
 
     if lo < 0:
         raise ValueError('lo must be non-negative')
-    if hi is None:
+    if hi is None or hi == -1:
         hi = len(a)
     while lo < hi:
         mid = (lo+hi)//2

diff --git a/Lib/test/test_bisect.py b/Lib/test/test_bisect.py
@@ -186,6 +186,11 @@ def test_optionalSlicing(self):
                         self.assertTrue(data[ip-1] <= elem)
                     self.assertEqual(ip, max(lo, min(hi, expected)))
 
+    def test_hi_backcompatbility(self):
+        for func, data, elem, expected in self.precomputedCases:
+            self.assertEqual(func(data, elem, 0, -1),
+                             func(data, elem, 0, None))
+
     def test_backcompatibility(self):
         self.assertEqual(self.module.bisect, self.module.bisect_right)
 

diff --git a/Modules/_bisectmodule.c b/Modules/_bisectmodule.c
@@ -6,6 +6,39 @@ Converted to C by Dmitry Vasiliev (dima at hlabs.spb.ru).
 #define PY_SSIZE_T_CLEAN
 #include "Python.h"
 
+static int
+ssize_t_converter(PyObject *obj, void *ptr)
+{
+    Py_ssize_t val;
+
+    val = PyLong_AsSsize_t(obj);
+    if (val == -1 && PyErr_Occurred()) {
+        return 0;
+    }
+    *(Py_ssize_t *)ptr = val;
+    return 1;
+}
+
+static int
+optional_ssize_t_converter(PyObject *obj, void *ptr)
+{
+    if (obj != Py_None) {
+        return ssize_t_converter(obj, ptr);
+    }
+    else {
+        *(Py_ssize_t *)ptr = -1;
+        return 1;
+    }
+}
+
+
+#include "clinic/_bisectmodule.c.h"
+
+/*[clinic input]
+module bisect
+[clinic start generated code]*/
+/*[clinic end generated code: output=da39a3ee5e6b4b0d input=d0e256c42a9e4c13]*/
+
 _Py_IDENTIFIER(insert);
 
 static Py_ssize_t
@@ -44,56 +77,79 @@ internal_bisect_right(PyObject *list, PyObject *item, Py_ssize_t lo, Py_ssize_t
     return lo;
 }
 
+/*[python input]
+class hi_parameter_converter(CConverter):
+    type = 'Py_ssize_t'
+    converter = 'optional_ssize_t_converter'
+
+[python start generated code]*/
+/*[python end generated code: output=da39a3ee5e6b4b0d input=53c711121eb30d3f]*/
+
+
+/*[clinic input]
+bisect.bisect_right
+
+    a: object
+    x: object
+    lo: Py_ssize_t(c_default='0') = 0
+    hi: hi_parameter(c_default='-1') = None
+
+Return the index where to insert item x in list a, assuming a is sorted.
+
+The return value i is such that all e in a[:i] have e <= x, and all e in
+a[i:] have e > x.  So if x already appears in the list, i points just
+beyond the rightmost x already there.
+
+Optional args lo (default 0) and hi (default len(a)) bound the
+slice of a to be searched.
+[clinic start generated code]*/
+
 static PyObject *
-bisect_right(PyObject *self, PyObject *args, PyObject *kw)
+bisect_bisect_right_impl(PyObject *module, PyObject *a, PyObject *x,
+                         Py_ssize_t lo, Py_ssize_t hi)
+/*[clinic end generated code: output=a2fb3e3261e46954 input=94e1e505e7f1ced8]*/
 {
-    PyObject *list, *item;
-    Py_ssize_t lo = 0;
-    Py_ssize_t hi = -1;
     Py_ssize_t index;
-    static char *keywords[] = {"a", "x", "lo", "hi", NULL};
 
-    if (!PyArg_ParseTupleAndKeywords(args, kw, "OO|nn:bisect_right",
-        keywords, &list, &item, &lo, &hi))
-        return NULL;
-    index = internal_bisect_right(list, item, lo, hi);
+    index = internal_bisect_right(a, x, lo, hi);
     if (index < 0)
         return NULL;
     return PyLong_FromSsize_t(index);
 }
 
-PyDoc_STRVAR(bisect_right_doc,
-"bisect_right(a, x[, lo[, hi]]) -> index\n\
-\n\
-Return the index where to insert item x in list a, assuming a is sorted.\n\
-\n\
-The return value i is such that all e in a[:i] have e <= x, and all e in\n\
-a[i:] have e > x.  So if x already appears in the list, i points just\n\
-beyond the rightmost x already there\n\
-\n\
-Optional args lo (default 0) and hi (default len(a)) bound the\n\
-slice of a to be searched.\n");
+/*[clinic input]
+bisect.insort_right
+
+    a: object
+    x: object
+    lo: Py_ssize_t(c_default='0') = 0
+    hi: hi_parameter(c_default='-1') = None
+
+Insert item x in list a, and keep it sorted assuming a is sorted.
+
+If x is already in a, insert it to the right of the rightmost x.
+
+Optional args lo (default 0) and hi (default len(a)) bound the
+slice of a to be searched.
+
+[clinic start generated code]*/
 
 static PyObject *
-insort_right(PyObject *self, PyObject *args, PyObject *kw)
+bisect_insort_right_impl(PyObject *module, PyObject *a, PyObject *x,
+                         Py_ssize_t lo, Py_ssize_t hi)
+/*[clinic end generated code: output=6e0b99c731a11c1a input=6790b22da4643197]*/
 {
-    PyObject *list, *item, *result;
-    Py_ssize_t lo = 0;
-    Py_ssize_t hi = -1;
+    PyObject *result;
     Py_ssize_t index;
-    static char *keywords[] = {"a", "x", "lo", "hi", NULL};
 
-    if (!PyArg_ParseTupleAndKeywords(args, kw, "OO|nn:insort_right",
-        keywords, &list, &item, &lo, &hi))
-        return NULL;
-    index = internal_bisect_right(list, item, lo, hi);
+    index = internal_bisect_right(a, x, lo, hi);
     if (index < 0)
         return NULL;
-    if (PyList_CheckExact(list)) {
-        if (PyList_Insert(list, index, item) < 0)
+    if (PyList_CheckExact(a)) {
+        if (PyList_Insert(a, index, x) < 0)
             return NULL;
     } else {
-        result = _PyObject_CallMethodId(list, &PyId_insert, "nO", index, item);
+        result = _PyObject_CallMethodId(a, &PyId_insert, "nO", index, x);
         if (result == NULL)
             return NULL;
         Py_DECREF(result);
@@ -102,16 +158,6 @@ insort_right(PyObject *self, PyObject *args, PyObject *kw)
     Py_RETURN_NONE;
 }
 
-PyDoc_STRVAR(insort_right_doc,
-"insort_right(a, x[, lo[, hi]])\n\
-\n\
-Insert item x in list a, and keep it sorted assuming a is sorted.\n\
-\n\
-If x is already in a, insert it to the right of the rightmost x.\n\
-\n\
-Optional args lo (default 0) and hi (default len(a)) bound the\n\
-slice of a to be searched.\n");
-
 static Py_ssize_t
 internal_bisect_left(PyObject *list, PyObject *item, Py_ssize_t lo, Py_ssize_t hi)
 {
@@ -148,56 +194,71 @@ internal_bisect_left(PyObject *list, PyObject *item, Py_ssize_t lo, Py_ssize_t h
     return lo;
 }
 
+/*[clinic input]
+bisect.bisect_left
+
+    a: object
+    x: object
+    lo: Py_ssize_t(c_default='0') = 0
+    hi: hi_parameter(c_default='-1') = None
+
+Return the index where to insert item x in list a, assuming a is sorted.
+
+The return value i is such that all e in a[:i] have e < x, and all e in
+a[i:] have e >= x.  So if x already appears in the list, i points just
+before the leftmost x already there.
+
+Optional args lo (default 0) and hi (default len(a)) bound the
+slice of a to be searched.
+
+[clinic start generated code]*/
+
 static PyObject *
-bisect_left(PyObject *self, PyObject *args, PyObject *kw)
+bisect_bisect_left_impl(PyObject *module, PyObject *a, PyObject *x,
+                        Py_ssize_t lo, Py_ssize_t hi)
+/*[clinic end generated code: output=27a0228c4a0a5fa2 input=fc1e8f6081ccfd7c]*/
 {
-    PyObject *list, *item;
-    Py_ssize_t lo = 0;
-    Py_ssize_t hi = -1;
     Py_ssize_t index;
-    static char *keywords[] = {"a", "x", "lo", "hi", NULL};
 
-    if (!PyArg_ParseTupleAndKeywords(args, kw, "OO|nn:bisect_left",
-        keywords, &list, &item, &lo, &hi))
-        return NULL;
-    index = internal_bisect_left(list, item, lo, hi);
+    index = internal_bisect_left(a, x, lo, hi);
     if (index < 0)
         return NULL;
     return PyLong_FromSsize_t(index);
 }
 
-PyDoc_STRVAR(bisect_left_doc,
-"bisect_left(a, x[, lo[, hi]]) -> index\n\
-\n\
-Return the index where to insert item x in list a, assuming a is sorted.\n\
-\n\
-The return value i is such that all e in a[:i] have e < x, and all e in\n\
-a[i:] have e >= x.  So if x already appears in the list, i points just\n\
-before the leftmost x already there.\n\
-\n\
-Optional args lo (default 0) and hi (default len(a)) bound the\n\
-slice of a to be searched.\n");
+/*[clinic input]
+bisect.insort_left
+
+    a: object
+    x: object
+    lo: Py_ssize_t(c_default='0') = 0
+    hi: hi_parameter(c_default='-1') = None
+
+Insert item x in list a, and keep it sorted assuming a is sorted.
+
+If x is already in a, insert it to the left of the leftmost x.
+
+Optional args lo (default 0) and hi (default len(a)) bound the
+slice of a to be searched.
+
+[clinic start generated code]*/
 
 static PyObject *
-insort_left(PyObject *self, PyObject *args, PyObject *kw)
+bisect_insort_left_impl(PyObject *module, PyObject *a, PyObject *x,
+                        Py_ssize_t lo, Py_ssize_t hi)
+/*[clinic end generated code: output=aa0228af6970ec52 input=582456c4727c5716]*/
 {
-    PyObject *list, *item, *result;
-    Py_ssize_t lo = 0;
-    Py_ssize_t hi = -1;
+    PyObject *result;
     Py_ssize_t index;
-    static char *keywords[] = {"a", "x", "lo", "hi", NULL};
 
-    if (!PyArg_ParseTupleAndKeywords(args, kw, "OO|nn:insort_left",
-        keywords, &list, &item, &lo, &hi))
-        return NULL;
-    index = internal_bisect_left(list, item, lo, hi);
+    index = internal_bisect_left(a, x, lo, hi);
     if (index < 0)
         return NULL;
-    if (PyList_CheckExact(list)) {
-        if (PyList_Insert(list, index, item) < 0)
+    if (PyList_CheckExact(a)) {
+        if (PyList_Insert(a, index, x) < 0)
             return NULL;
     } else {
-        result = _PyObject_CallMethodId(list, &PyId_insert, "nO", index, item);
+        result = _PyObject_CallMethodId(a, &PyId_insert, "nO", index, x);
         if (result == NULL)
             return NULL;
         Py_DECREF(result);
@@ -206,25 +267,11 @@ insort_left(PyObject *self, PyObject *args, PyObject *kw)
     Py_RETURN_NONE;
 }
 
-PyDoc_STRVAR(insort_left_doc,
-"insort_left(a, x[, lo[, hi]])\n\
-\n\
-Insert item x in list a, and keep it sorted assuming a is sorted.\n\
-\n\
-If x is already in a, insert it to the left of the leftmost x.\n\
-\n\
-Optional args lo (default 0) and hi (default len(a)) bound the\n\
-slice of a to be searched.\n");
-
 static PyMethodDef bisect_methods[] = {
-    {"bisect_right", (PyCFunction)bisect_right,
-        METH_VARARGS|METH_KEYWORDS, bisect_right_doc},
-    {"insort_right", (PyCFunction)insort_right,
-        METH_VARARGS|METH_KEYWORDS, insort_right_doc},
-    {"bisect_left", (PyCFunction)bisect_left,
-        METH_VARARGS|METH_KEYWORDS, bisect_left_doc},
-    {"insort_left", (PyCFunction)insort_left,
-        METH_VARARGS|METH_KEYWORDS, insort_left_doc},
+    BISECT_BISECT_RIGHT_METHODDEF
+    BISECT_INSORT_RIGHT_METHODDEF
+    BISECT_BISECT_LEFT_METHODDEF
+    BISECT_INSORT_LEFT_METHODDEF
     {NULL, NULL} /* sentinel */
 };