start removal of six and improve type annotation (#607)

* fix unfinished Python2 -> 3 translation
* remove some six usage
* annotate
* fix regression in Six removal
* mypy: self.enf is always defined
* fix return type of cups.py
* Usb idVendor/idProduct are integers
* self.default_args is always defined
* tweak usb_args, PEP589 is better
* lp.py: reassure mypy
* correctly cast call to CashDrawerError()
* update CUPS test
* add missing close() method in metaclass
* document a bug in typeshed
* query_status() returns bytes as seen in constants.py
* remove more SIX usage
* test examples too
* remove type comment where type is annotated
* adapt behavior of cups printer to match other implementations

---------

Co-authored-by: Patrick Kanzler <dev@pkanzler.de>
Co-authored-by: Patrick Kanzler <4189642+patkan@users.noreply.github.com>

examples/codepage_tables.py

@@ -3,8 +3,6 @@
 
 import sys
 
-import six
-
 from escpos import printer
 from escpos.constants import (
     CODEPAGE_CHANGE,
@@ -38,7 +36,7 @@ def print_codepage(printer, codepage):
     """Print a codepage."""
     if codepage.isdigit():
         codepage = int(codepage)
-        printer._raw(CODEPAGE_CHANGE + six.int2byte(codepage))
+        printer._raw(CODEPAGE_CHANGE + bytes((codepage,)))
         printer._raw("after")
     else:
         printer.charcode(codepage)
@@ -58,7 +56,9 @@ def print_codepage(printer, codepage):
         printer.set()
 
         for y in range(0, 16):
-            byte = six.int2byte(x * 16 + y)
+            byte = bytes(
+                (x * 16 + y),
+            )
 
             if byte in (ESC, CTL_LF, CTL_FF, CTL_CR, CTL_HT, CTL_VT):
                 byte = " "