bpo-41334: Convert constructors of str, bytes and bytearray to Argument Clinic (GH-21535)

diff --git a/Objects/clinic/unicodeobject.c.h b/Objects/clinic/unicodeobject.c.h
index ecd409e..9ef8ce2 100644
--- a/Objects/clinic/unicodeobject.c.h
+++ b/Objects/clinic/unicodeobject.c.h
@@ -1258,4 +1258,73 @@
 {
     return unicode_sizeof_impl(self);
 }
-/*[clinic end generated code: output=c5eb21e314da78b8 input=a9049054013a1b77]*/
+
+static PyObject *
+unicode_new_impl(PyTypeObject *type, PyObject *x, const char *encoding,
+                 const char *errors);
+
+static PyObject *
+unicode_new(PyTypeObject *type, PyObject *args, PyObject *kwargs)
+{
+    PyObject *return_value = NULL;
+    static const char * const _keywords[] = {"object", "encoding", "errors", NULL};
+    static _PyArg_Parser _parser = {NULL, _keywords, "str", 0};
+    PyObject *argsbuf[3];
+    PyObject * const *fastargs;
+    Py_ssize_t nargs = PyTuple_GET_SIZE(args);
+    Py_ssize_t noptargs = nargs + (kwargs ? PyDict_GET_SIZE(kwargs) : 0) - 0;
+    PyObject *x = NULL;
+    const char *encoding = NULL;
+    const char *errors = NULL;
+
+    fastargs = _PyArg_UnpackKeywords(_PyTuple_CAST(args)->ob_item, nargs, kwargs, NULL, &_parser, 0, 3, 0, argsbuf);
+    if (!fastargs) {
+        goto exit;
+    }
+    if (!noptargs) {
+        goto skip_optional_pos;
+    }
+    if (fastargs[0]) {
+        x = fastargs[0];
+        if (!--noptargs) {
+            goto skip_optional_pos;
+        }
+    }
+    if (fastargs[1]) {
+        if (!PyUnicode_Check(fastargs[1])) {
+            _PyArg_BadArgument("str", "argument 'encoding'", "str", fastargs[1]);
+            goto exit;
+        }
+        Py_ssize_t encoding_length;
+        encoding = PyUnicode_AsUTF8AndSize(fastargs[1], &encoding_length);
+        if (encoding == NULL) {
+            goto exit;
+        }
+        if (strlen(encoding) != (size_t)encoding_length) {
+            PyErr_SetString(PyExc_ValueError, "embedded null character");
+            goto exit;
+        }
+        if (!--noptargs) {
+            goto skip_optional_pos;
+        }
+    }
+    if (!PyUnicode_Check(fastargs[2])) {
+        _PyArg_BadArgument("str", "argument 'errors'", "str", fastargs[2]);
+        goto exit;
+    }
+    Py_ssize_t errors_length;
+    errors = PyUnicode_AsUTF8AndSize(fastargs[2], &errors_length);
+    if (errors == NULL) {
+        goto exit;
+    }
+    if (strlen(errors) != (size_t)errors_length) {
+        PyErr_SetString(PyExc_ValueError, "embedded null character");
+        goto exit;
+    }
+skip_optional_pos:
+    return_value = unicode_new_impl(type, x, encoding, errors);
+
+exit:
+    return return_value;
+}
+/*[clinic end generated code: output=f10cf85d3935b3b7 input=a9049054013a1b77]*/