remove psutil.test() ps-like function

It could not be called anymore via:

$ python3 -m psutil
/usr/bin/python3: No module named psutil.__main__; 'psutil' is a package and cannot be directly executed

...plus code it's a duplicate of scripts/ps.py.

psutil/__init__.py

@@ -2395,82 +2395,4 @@ def _set_debug(value):
     _psplatform.cext.set_debug(bool(value))
 
 
-def test():  # pragma: no cover
-    import shutil
-
-    from ._common import bytes2human
-
-    today_day = datetime.date.today()
-    # fmt: off
-    templ = "%-10s %5s %5s %7s %7s %5s %6s %6s %6s  %s"
-    attrs = ['pid', 'memory_percent', 'name', 'cmdline', 'cpu_times',
-             'create_time', 'memory_info', 'status', 'nice', 'username']
-    print(templ % ("USER", "PID", "%MEM", "VSZ", "RSS", "NICE",  # NOQA
-                   "STATUS", "START", "TIME", "CMDLINE"))
-    # fmt: on
-    for p in process_iter(attrs, ad_value=None):
-        if p.info['create_time']:
-            ctime = datetime.datetime.fromtimestamp(p.info['create_time'])
-            if ctime.date() == today_day:
-                ctime = ctime.strftime("%H:%M")
-            else:
-                ctime = ctime.strftime("%b%d")
-        else:
-            ctime = ''
-        if p.info['cpu_times']:
-            cputime = time.strftime(
-                "%M:%S", time.localtime(sum(p.info['cpu_times']))
-            )
-        else:
-            cputime = ''
-
-        user = p.info['username'] or ''
-        if not user and POSIX:
-            try:
-                user = p.uids()[0]
-            except Error:
-                pass
-        if user and WINDOWS and '\\' in user:
-            user = user.split('\\')[1]
-        user = user[:9]
-        vms = (
-            bytes2human(p.info['memory_info'].vms)
-            if p.info['memory_info'] is not None
-            else ''
-        )
-        rss = (
-            bytes2human(p.info['memory_info'].rss)
-            if p.info['memory_info'] is not None
-            else ''
-        )
-        memp = (
-            round(p.info['memory_percent'], 1)
-            if p.info['memory_percent'] is not None
-            else ''
-        )
-        nice = int(p.info['nice']) if p.info['nice'] else ''
-        if p.info['cmdline']:
-            cmdline = ' '.join(p.info['cmdline'])
-        else:
-            cmdline = p.info['name']
-        status = p.info['status'][:5] if p.info['status'] else ''
-
-        line = templ % (
-            user[:10],
-            p.info['pid'],
-            memp,
-            vms,
-            rss,
-            nice,
-            status,
-            ctime,
-            cputime,
-            cmdline,
-        )
-        print(line[: shutil.get_terminal_size()[0]])  # NOQA
-
-
 del memoize_when_activated
-
-if __name__ == "__main__":
-    test()

psutil/tests/test_system.py

@@ -32,7 +32,6 @@
 from psutil import WINDOWS
 from psutil.tests import ASCII_FS
 from psutil.tests import CI_TESTING
-from psutil.tests import DEVNULL
 from psutil.tests import GITHUB_ACTIONS
 from psutil.tests import GLOBAL_TIMEOUT
 from psutil.tests import HAS_BATTERY
@@ -261,15 +260,6 @@ def test_users(self):
                 else:
                     psutil.Process(user.pid)
 
-    def test_test(self):
-        # test for psutil.test() function
-        stdout = sys.stdout
-        sys.stdout = DEVNULL
-        try:
-            psutil.test()
-        finally:
-            sys.stdout = stdout
-
     def test_os_constants(self):
         names = [
             "POSIX",