diff --git a/httpheaders.py b/httpheaders.py
index 9b552cfa9..367932e9f 100644
--- a/httpheaders.py
+++ b/httpheaders.py
@@ -10,6 +10,7 @@ __module_group__ = "Core"
 import os
 import urllib.parse
 from hashlib import md5
+from utils import string_contains
 from utils import get_instance_url
 
 
@@ -121,9 +122,7 @@ def _set_headers_base(self, file_format: str, length: int, cookie: str,
                       calling_domain: str, permissive: bool) -> None:
     self.send_response(200)
     self.send_header('Content-type', file_format)
-    if 'image/' in file_format or \
-       'audio/' in file_format or \
-       'video/' in file_format:
+    if string_contains(file_format, ('image/', 'audio/', 'video/')):
         cache_control = 'public, max-age=84600, immutable'
         self.send_header('Cache-Control', cache_control)
     else:
diff --git a/mastoapiv1.py b/mastoapiv1.py
index e960f257e..0beafa807 100644
--- a/mastoapiv1.py
+++ b/mastoapiv1.py
@@ -8,6 +8,7 @@ __status__ = "Production"
 __module_group__ = "API"
 
 import os
+from utils import string_contains
 from utils import get_url_from_post
 from utils import load_json
 from utils import get_config_param
@@ -346,12 +347,9 @@ def masto_api_v1_response(path: str, calling_domain: str,
         path_nickname = get_nickname_from_masto_api_v1id(masto_id)
         if path_nickname:
             original_path = path
-            if '/followers?' in path or \
-               '/following?' in path or \
-               '/streaming/' in path or \
-               '/search?' in path or \
-               '/relationships?' in path or \
-               '/statuses?' in path:
+            if string_contains(path,
+                               ('/followers?', '/following?', '/streaming/',
+                                '/search?', '/relationships?', '/statuses?')):
                 path = path.split('?')[0]
             if '/streaming/' in path:
                 streaming_msg = \
diff --git a/newswire.py b/newswire.py
index 85ef0ff6f..36e94e294 100644
--- a/newswire.py
+++ b/newswire.py
@@ -19,6 +19,7 @@ from datetime import timezone
 from collections import OrderedDict
 from utils import valid_post_date
 from categories import set_hashtag_category
+from utils import string_contains
 from utils import image_mime_types_dict
 from utils import resembles_url
 from utils import get_url_from_post
@@ -667,9 +668,9 @@ def xml_podcast_to_dict(base_dir: str, xml_item: str, xml_str: str) -> {}:
         podcast_properties['image'] = podcast_episode_image
         podcast_properties['categories'] = podcast_categories
 
-        if '<itunes:explicit>Y' in xml_item or \
-           '<itunes:explicit>T' in xml_item or \
-           '<itunes:explicit>1' in xml_item:
+        if string_contains(xml_item,
+                           ('<itunes:explicit>Y', '<itunes:explicit>T',
+                            '<itunes:explicit>1')):
             podcast_properties['explicit'] = True
         else:
             podcast_properties['explicit'] = False
diff --git a/posts.py b/posts.py
index 58c6927eb..149f6ee54 100644
--- a/posts.py
+++ b/posts.py
@@ -34,6 +34,7 @@ from webfinger import webfinger_handle
 from httpsig import create_signed_header
 from siteactive import site_is_active
 from languages import understood_post_language
+from utils import string_contains
 from utils import get_post_attachments
 from utils import is_premium_account
 from utils import contains_private_key
@@ -793,12 +794,7 @@ def _update_word_frequency(content: str, word_frequency: {}) -> None:
         if word_len < 4:
             if word.upper() != word:
                 continue
-        if '&' in word or \
-           '"' in word or \
-           '@' in word or \
-           "'" in word or \
-           "--" in word or \
-           '//' in word:
+        if string_contains(word, ('&', '"', '@', "'", "--", '//')):
             continue
         if word.lower() in common_words:
             continue
@@ -4447,13 +4443,9 @@ def _add_post_string_to_timeline(post_str: str, boxname: str,
     """ is this a valid timeline post?
     """
     # must be a recognized ActivityPub type
-    if ('"Note"' in post_str or
-        '"EncryptedMessage"' in post_str or
-        '"ChatMessage"' in post_str or
-        '"Event"' in post_str or
-        '"Article"' in post_str or
-        '"Patch"' in post_str or
-        '"Announce"' in post_str or
+    if (string_contains(post_str,
+                        ('"Note"', '"EncryptedMessage"', '"ChatMessage"',
+                         '"Event"', '"Article"', '"Patch"', '"Announce"')) or
         ('"Question"' in post_str and
          ('"Create"' in post_str or '"Update"' in post_str))):
 
diff --git a/webapp_utils.py b/webapp_utils.py
index e202e21ef..f465ea90d 100644
--- a/webapp_utils.py
+++ b/webapp_utils.py
@@ -12,6 +12,7 @@ from shutil import copyfile
 from collections import OrderedDict
 from session import get_json
 from session import get_json_valid
+from utils import string_contains
 from utils import get_post_attachments
 from utils import image_mime_types_dict
 from utils import get_url_from_post
@@ -2338,9 +2339,7 @@ def get_buy_links(post_json_object: str, translate: {}, buy_sites: {}) -> {}:
         if remove_html(item_name) != item_name:
             continue
         # there should be no html in the link
-        if '<' in item['href'] or \
-           '://' not in item['href'] or \
-           ' ' in item['href']:
+        if string_contains(item['href'], ('<', '://', ' ')):
             continue
         if item.get('rel'):
             if isinstance(item['rel'], str):