How to use the py.builtin._totext function in py

def sysexec(self, *argv, **popen_opts):
        """ return stdout text from executing a system child process,
            where the 'self' path points to executable.
            The process is directly invoked and not through a system shell.
        """
        from subprocess import Popen, PIPE
        argv = map_as_list(str, argv)
        popen_opts['stdout'] = popen_opts['stderr'] = PIPE
        proc = Popen([str(self)] + argv, **popen_opts)
        stdout, stderr = proc.communicate()
        ret = proc.wait()
        if py.builtin._isbytes(stdout):
            stdout = py.builtin._totext(stdout, sys.getdefaultencoding())
        if ret != 0:
            if py.builtin._isbytes(stderr):
                stderr = py.builtin._totext(stderr, sys.getdefaultencoding())
            raise py.process.cmdexec.Error(ret, ret, str(self),
                                           stdout, stderr,)
        return stdout

def _makefile(self, ext, args, kwargs):
        items = list(kwargs.items())
        if args:
            source = py.builtin._totext("\n").join(
                map(py.builtin._totext, args)) + py.builtin._totext("\n")
            basename = self.request.function.__name__
            items.insert(0, (basename, source))
        ret = None
        for name, value in items:
            p = self.tmpdir.join(name).new(ext=ext)
            source = Source(value)
            def my_totext(s, encoding="utf-8"):
                if py.builtin._isbytes(s):
                    s = py.builtin._totext(s, encoding=encoding)
                return s
            source_unicode = "\n".join([my_totext(line) for line in source.lines])
            source = py.builtin._totext(source_unicode)
            content = source.strip().encode("utf-8") # + "\n"
            #content = content.rstrip() + "\n"
            p.write(content, "wb")
            if ret is None:

items = list(kwargs.items())
        if args:
            source = py.builtin._totext("\n").join(
                map(py.builtin._totext, args)) + py.builtin._totext("\n")
            basename = self.request.function.__name__
            items.insert(0, (basename, source))
        ret = None
        for name, value in items:
            p = self.tmpdir.join(name).new(ext=ext)
            source = Source(value)
            def my_totext(s, encoding="utf-8"):
                if py.builtin._isbytes(s):
                    s = py.builtin._totext(s, encoding=encoding)
                return s
            source_unicode = "\n".join([my_totext(line) for line in source.lines])
            source = py.builtin._totext(source_unicode)
            content = source.strip().encode("utf-8") # + "\n"
            #content = content.rstrip() + "\n"
            p.write(content, "wb")
            if ret is None:
                ret = p
        return ret

"""Utilities for assertion debugging"""
import pprint

import _pytest._code
import py
try:
    from collections import Sequence
except ImportError:
    Sequence = list

BuiltinAssertionError = py.builtin.builtins.AssertionError
u = py.builtin._totext

# The _reprcompare attribute on the util module is used by the new assertion
# interpretation code and assertion rewriter to detect this plugin was
# loaded and in turn call the hooks defined here as part of the
# DebugInterpreter.
_reprcompare = None


# the re-encoding is needed for python2 repr
# with non-ascii characters (see issue 877 and 1379)
def ecu(s):
    try:
        return u(s, 'utf-8', 'replace')
    except TypeError:
        return s

def _makefile(self, ext, args, kwargs):
        items = list(kwargs.items())
        if args:
            source = py.builtin._totext("\n").join(
                map(py.builtin._totext, args)) + py.builtin._totext("\n")
            basename = self.request.function.__name__
            items.insert(0, (basename, source))
        ret = None
        for name, value in items:
            p = self.tmpdir.join(name).new(ext=ext)
            source = Source(value)
            def my_totext(s, encoding="utf-8"):
                if py.builtin._isbytes(s):
                    s = py.builtin._totext(s, encoding=encoding)
                return s
            source_unicode = "\n".join([my_totext(line) for line in source.lines])
            source = py.builtin._totext(source_unicode)
            content = source.strip().encode("utf-8") # + "\n"
            #content = content.rstrip() + "\n"
            p.write(content, "wb")

def test_capturing_readouterr_decode_error_handling(self):
        cap = self.getcapture()
        # triggered a internal error in pytest
        print('\xa6')
        out, err = cap.readouterr()
        assert out == py.builtin._totext('\ufffd\n', 'unicode-escape')

def snap(self):
        f = self.tmpfile
        f.seek(0)
        res = f.read()
        if res:
            enc = getattr(f, "encoding", None)
            if enc and isinstance(res, bytes):
                res = py.builtin._totext(res, enc, "replace")
            f.truncate(0)
            f.seek(0)
            return res
        return ''

def test_unicode_on_file_with_ascii_encoding(tmpdir, monkeypatch, encoding):
    msg = py.builtin._totext('hell\xf6', "latin1")
    #pytest.raises(UnicodeEncodeError, lambda: bytes(msg))
    f = py.std.codecs.open(str(tmpdir.join("x")), "w", encoding)
    tw = py.io.TerminalWriter(f)
    tw.line(msg)
    f.close()
    s = tmpdir.join("x").open("rb").read().strip()
    assert encoding == "ascii"
    assert s == msg.encode("unicode-escape")

def test_update(self, keyfs):
        key1 = keyfs.add_key("NAME1", "some1", dict)
        key2 = keyfs.add_key("NAME2", "some2", list)
        keyfs.restart_as_write_transaction()
        with key1.update() as d:
            with key2.update() as l:
                l.append(1)
                d[py.builtin._totext("hello")] = l
        assert key1.get()["hello"] == l

def newsalt():
    return py.builtin._totext(base64.b64encode(os.urandom(16)), "ascii")