Fix pycodestyle complaints

Apparently, pycodestyle updated itself to now check for invalid escape
sequences, which only complain if the regex in use isn't a raw string
(r"").

src/documents/models.py

@@ -135,7 +135,7 @@ class MatchingModel(models.Model):
         Example:
           '  some random  words "with   quotes  " and   spaces'
             ==>
-          ["some", "random", "words", "with\s+quotes", "and", "spaces"]
+          ["some", "random", "words", "with+quotes", "and", "spaces"]
         """
         findterms = re.compile(r'"([^"]+)"|(\S+)').findall
         normspace = re.compile(r"\s+").sub

src/documents/tests/test_matchables.py

@@ -166,7 +166,7 @@ class TestMatching(TestCase):
     def test_match_regex(self):
 
         self._test_matching(
-            "alpha\w+gamma",
+            r"alpha\w+gamma",
             "MATCH_REGEX",
             (
                 "I have alpha_and_gamma in me",

src/paperless_tesseract/parsers.py

@@ -272,8 +272,9 @@ def run_unpaper(args):
 def strip_excess_whitespace(text):
     collapsed_spaces = re.sub(r"([^\S\r\n]+)", " ", text)
     no_leading_whitespace = re.sub(
-        "([\n\r]+)([^\S\n\r]+)", '\\1', collapsed_spaces)
+        r"([\n\r]+)([^\S\n\r]+)", '\\1', collapsed_spaces)
-    no_trailing_whitespace = re.sub("([^\S\n\r]+)$", '', no_leading_whitespace)
+    no_trailing_whitespace = re.sub(
+        r"([^\S\n\r]+)$", '', no_leading_whitespace)
     return no_trailing_whitespace
 
 

src/paperless_tesseract/signals.py

@@ -5,7 +5,7 @@ from .parsers import RasterisedDocumentParser
 
 class ConsumerDeclaration:
 
-    MATCHING_FILES = re.compile("^.*\.(pdf|jpe?g|gif|png|tiff?|pnm|bmp)$")
+    MATCHING_FILES = re.compile(r"^.*\.(pdf|jpe?g|gif|png|tiff?|pnm|bmp)$")
 
     @classmethod
     def handle(cls, sender, **kwargs):