Fixed #28982 -- Simplified code with and/or.

7 files changed, 10 insertions, 20 deletions

diff --git a/django/utils/cache.py b/django/utils/cache.py
index ce7faaedbc..cb49806ee9 100644
--- a/django/utils/cache.py
+++ b/django/utils/cache.py
@@ -142,12 +142,10 @@ def get_conditional_response(request, etag=None, last_modified=None, response=No
     # Get HTTP request headers.
     if_match_etags = parse_etags(request.META.get('HTTP_IF_MATCH', ''))
     if_unmodified_since = request.META.get('HTTP_IF_UNMODIFIED_SINCE')
-    if if_unmodified_since:
-        if_unmodified_since = parse_http_date_safe(if_unmodified_since)
+    if_unmodified_since = if_unmodified_since and parse_http_date_safe(if_unmodified_since)
     if_none_match_etags = parse_etags(request.META.get('HTTP_IF_NONE_MATCH', ''))
     if_modified_since = request.META.get('HTTP_IF_MODIFIED_SINCE')
-    if if_modified_since:
-        if_modified_since = parse_http_date_safe(if_modified_since)
+    if_modified_since = if_modified_since and parse_http_date_safe(if_modified_since)
 
     # Step 1 of section 6 of RFC 7232: Test the If-Match precondition.
     if if_match_etags and not _if_match_passes(etag, if_match_etags):
diff --git a/django/utils/crypto.py b/django/utils/crypto.py
index f6f44856d0..61d02b65cf 100644
--- a/django/utils/crypto.py
+++ b/django/utils/crypto.py
@@ -78,8 +78,7 @@ def pbkdf2(password, salt, iterations, dklen=0, digest=None):
     """Return the hash of password using pbkdf2."""
     if digest is None:
         digest = hashlib.sha256
-    if not dklen:
-        dklen = None
+    dklen = dklen or None
     password = force_bytes(password)
     salt = force_bytes(salt)
     return hashlib.pbkdf2_hmac(digest().name, password, salt, iterations, dklen)
diff --git a/django/utils/dateparse.py b/django/utils/dateparse.py
index e0e5e244c7..8d08b7d1d3 100644
--- a/django/utils/dateparse.py
+++ b/django/utils/dateparse.py
@@ -89,8 +89,7 @@ def parse_time(value):
     match = time_re.match(value)
     if match:
         kw = match.groupdict()
-        if kw['microsecond']:
-            kw['microsecond'] = kw['microsecond'].ljust(6, '0')
+        kw['microsecond'] = kw['microsecond'] and kw['microsecond'].ljust(6, '0')
         kw = {k: int(v) for k, v in kw.items() if v is not None}
         return datetime.time(**kw)
 
@@ -107,8 +106,7 @@ def parse_datetime(value):
     match = datetime_re.match(value)
     if match:
         kw = match.groupdict()
-        if kw['microsecond']:
-            kw['microsecond'] = kw['microsecond'].ljust(6, '0')
+        kw['microsecond'] = kw['microsecond'] and kw['microsecond'].ljust(6, '0')
         tzinfo = kw.pop('tzinfo')
         if tzinfo == 'Z':
             tzinfo = utc
diff --git a/django/utils/deprecation.py b/django/utils/deprecation.py
index 07a7f853a9..1cb1df105c 100644
--- a/django/utils/deprecation.py
+++ b/django/utils/deprecation.py
@@ -88,8 +88,7 @@ class MiddlewareMixin:
         response = None
         if hasattr(self, 'process_request'):
             response = self.process_request(request)
-        if not response:
-            response = self.get_response(request)
+        response = response or self.get_response(request)
         if hasattr(self, 'process_response'):
             response = self.process_response(request, response)
         return response
diff --git a/django/utils/feedgenerator.py b/django/utils/feedgenerator.py
index a0f63901c7..7fc63f5adb 100644
--- a/django/utils/feedgenerator.py
+++ b/django/utils/feedgenerator.py
@@ -86,8 +86,7 @@ class SyndicationFeed:
                  feed_url=None, feed_copyright=None, feed_guid=None, ttl=None, **kwargs):
         def to_str(s):
             return str(s) if s is not None else s
-        if categories:
-            categories = [str(c) for c in categories]
+        categories = categories and [str(c) for c in categories]
         self.feed = {
             'title': to_str(title),
             'link': iri_to_uri(link),
@@ -117,8 +116,7 @@ class SyndicationFeed:
         """
         def to_str(s):
             return str(s) if s is not None else s
-        if categories:
-            categories = [to_str(c) for c in categories]
+        categories = categories and [to_str(c) for c in categories]
         self.items.append({
             'title': to_str(title),
             'link': iri_to_uri(link),
diff --git a/django/utils/numberformat.py b/django/utils/numberformat.py
index e910be9206..c6f9af6893 100644
--- a/django/utils/numberformat.py
+++ b/django/utils/numberformat.py
@@ -42,8 +42,7 @@ def format(number, decimal_sep, decimal_pos=None, grouping=0, thousand_sep='',
         int_part, dec_part = str_number, ''
     if decimal_pos is not None:
         dec_part = dec_part + ('0' * (decimal_pos - len(dec_part)))
-    if dec_part:
-        dec_part = decimal_sep + dec_part
+    dec_part = dec_part and decimal_sep + dec_part
     # grouping
     if use_grouping:
         try:
diff --git a/django/utils/timesince.py b/django/utils/timesince.py
index 8acfb6a484..1616c9a2ea 100644
--- a/django/utils/timesince.py
+++ b/django/utils/timesince.py
@@ -35,8 +35,7 @@ def timesince(d, now=None, reversed=False):
     if now and not isinstance(now, datetime.datetime):
         now = datetime.datetime(now.year, now.month, now.day)
 
-    if not now:
-        now = datetime.datetime.now(utc if is_aware(d) else None)
+    now = now or datetime.datetime.now(utc if is_aware(d) else None)
 
     if reversed:
         d, now = now, d