Fix deprecation warning regarding invalid escape sequences.

pretty_bad_protocol/_meta.py

@@ -54,7 +54,7 @@
 from ._parsers import _sanitise_list
 from ._util    import log
 
-_VERSION_RE = re.compile('^\d+\.\d+\.\d+$')
+_VERSION_RE = re.compile(r'^\d+\.\d+\.\d+$')
 
 
 class GPGMeta(type):

pretty_bad_protocol/_parsers.py

@@ -843,7 +843,7 @@ def __init__(self, expiration_time, passphrase=None):
 
     def _clean_key_expiration_option(self):
         """validates the expiration option supplied"""
-        allowed_entry = re.findall('^(\d+)(|w|m|y)$', self._expiration_time)
+        allowed_entry = re.findall(r'^(\d+)(|w|m|y)$', self._expiration_time)
         if not allowed_entry:
             raise UsageError("Key expiration option: %s is not valid" % self._expiration_time)
 

pretty_bad_protocol/_util.py

@@ -126,7 +126,7 @@
 log = _logger.create_logger(0)
 
 #: Compiled regex for determining a GnuPG binary's version:
-_VERSION_STRING_REGEX = re.compile('(\d)(\.)(\d)(\.)(\d+)')
+_VERSION_STRING_REGEX = re.compile(r'(\d)(\.)(\d)(\.)(\d+)')
 
 
 class GnuPGVersionError(ValueError):