revert most of the recent Pylint fixes

I know better how to name my things.

7 files changed, 88 insertions, 88 deletions

diff --git a/vk/last_seen.py b/vk/last_seen.py
index 1753e12..5266940 100644
--- a/vk/last_seen.py
+++ b/vk/last_seen.py
@@ -11,23 +11,23 @@ from numbers import Integral, Real
 
 from .platform import Platform
 
-def _parse_time(src):
-    if isinstance(src, datetime):
-        if src.tzinfo is None or src.tzinfo.utcoffset(src) is None:
-            src = src.replace(tzinfo=timezone.utc)
-        return src
-    elif isinstance(src, Real) or isinstance(src, Integral):
-        return datetime.fromtimestamp(src, tz=timezone.utc)
+def _parse_time(x):
+    if isinstance(x, datetime):
+        if x.tzinfo is None or x.tzinfo.utcoffset(x) is None:
+            x = x.replace(tzinfo=timezone.utc)
+        return x
+    elif isinstance(x, Real) or isinstance(x, Integral):
+        return datetime.fromtimestamp(x, tz=timezone.utc)
     else:
         raise TypeError()
 
-def _parse_platform(src):
-    if src in Platform:
-        return src
-    if isinstance(src, str):
-        return Platform.from_string(src)
+def _parse_platform(x):
+    if x in Platform:
+        return x
+    if isinstance(x, str):
+        return Platform.from_string(x)
     else:
-        return Platform(src)
+        return Platform(x)
 
 class LastSeenField(Enum):
     TIME = 'time'
@@ -85,8 +85,8 @@ class LastSeen(MutableMapping):
     def get_time(self):
         return self[LastSeenField.TIME]
 
-    def set_time(self, timestamp):
-        self[LastSeenField.TIME] = timestamp
+    def set_time(self, time):
+        self[LastSeenField.TIME] = time
 
     def has_platform(self):
         return LastSeenField.PLATFORM in self
diff --git a/vk/platform.py b/vk/platform.py
index 26f20dc..fa1e665 100644
--- a/vk/platform.py
+++ b/vk/platform.py
@@ -16,26 +16,26 @@ class Platform(Enum):
     WEB = 7
 
     @staticmethod
-    def from_string(src):
-        return Platform(int(src))
+    def from_string(s):
+        return Platform(int(s))
 
     def __str__(self):
         return str(self.value)
 
     @staticmethod
-    def _uppercase_first_letter(text):
-        match = re.search(r'\w', text)
-        if match is None:
-            return text
-        return text[:match.start()] + match.group().upper() + text[match.end():]
+    def _uppercase_first_letter(s):
+        m = re.search(r'\w', s)
+        if m is None:
+            return s
+        return s[:m.start()] + m.group().upper() + s[m.end():]
 
     def get_descr_header(self):
         return self._uppercase_first_letter(_PLATFORM_DESCRIPTIONS[self])
 
     def get_descr_text(self):
-        descr = _PLATFORM_DESCRIPTIONS[self]
-        descr = descr.replace('unrecognized', 'an unrecognized')
-        return 'the ' + descr
+        s = _PLATFORM_DESCRIPTIONS[self]
+        s = s.replace('unrecognized', 'an unrecognized')
+        return 'the ' + s
 
     def get_descr_text_capitalized(self):
         return self._uppercase_first_letter(self.get_descr_text())
diff --git a/vk/tracking/db/record.py b/vk/tracking/db/record.py
index 6c000ab..c03c3ca 100644
--- a/vk/tracking/db/record.py
+++ b/vk/tracking/db/record.py
@@ -38,9 +38,9 @@ class Record(MutableMapping):
     def __setitem__(self, field, value):
         if field is LastSeenField.TIME:
             if isinstance(value, str):
-                value = Timestamp.from_string(value).impl
+                value = Timestamp.from_string(value).dt
             elif isinstance(value, Timestamp):
-                value = value.impl
+                value = value.dt
             elif isinstance(value, datetime):
                 pass
             else:
@@ -78,7 +78,7 @@ class Record(MutableMapping):
 
     def _update_last_seen_field(self, last_seen, field):
         if field is LastSeenField.TIME:
-            last_seen[field] = self[field].impl
+            last_seen[field] = self[field].dt
         else:
             last_seen[field] = self[field]
 
diff --git a/vk/tracking/db/timestamp.py b/vk/tracking/db/timestamp.py
index 0881fb3..b2219ca 100644
--- a/vk/tracking/db/timestamp.py
+++ b/vk/tracking/db/timestamp.py
@@ -11,25 +11,25 @@ class Timestamp:
         return datetime.utcnow()
 
     @staticmethod
-    def _is_timezone_aware(impl):
-        return impl.tzinfo is not None and impl.tzinfo.utcoffset(impl) is not None
+    def _is_timezone_aware(dt):
+        return dt.tzinfo is not None and dt.tzinfo.utcoffset(dt) is not None
 
     @staticmethod
-    def _lose_timezone(impl):
-        if Timestamp._is_timezone_aware(impl):
-            return impl.astimezone(timezone.utc).replace(tzinfo=None)
-        return impl
+    def _lose_timezone(dt):
+        if Timestamp._is_timezone_aware(dt):
+            return dt.astimezone(timezone.utc).replace(tzinfo=None)
+        return dt
 
-    def __init__(self, impl=None):
-        if impl is None:
-            impl = self._new()
-        impl = impl.replace(microsecond=0)
-        impl = self._lose_timezone(impl)
-        self.impl = impl
+    def __init__(self, dt=None):
+        if dt is None:
+            dt = self._new()
+        dt = dt.replace(microsecond=0)
+        dt = self._lose_timezone(dt)
+        self.dt = dt
 
     @staticmethod
-    def from_string(src):
-        return Timestamp(datetime.strptime(src, '%Y-%m-%dT%H:%M:%SZ'))
+    def from_string(s):
+        return Timestamp(datetime.strptime(s, '%Y-%m-%dT%H:%M:%SZ'))
 
     def __str__(self):
-        return self.impl.isoformat() + 'Z'
+        return self.dt.isoformat() + 'Z'
diff --git a/vk/tracking/online_sessions.py b/vk/tracking/online_sessions.py
index 11d3196..204e1cc 100644
--- a/vk/tracking/online_sessions.py
+++ b/vk/tracking/online_sessions.py
@@ -99,20 +99,20 @@ class OnlineSessionEnumerator(MutableMapping):
         return by_hour
 
     @staticmethod
-    def _split_into_days(time_from, time_to):
-        while time_from.date() != time_to.date():
-            next_day = time_from.date() + timedelta(days=1)
-            yield time_from.date(), next_day - time_from
-            time_from = next_day
-        yield time_to.date(), time_to - time_from
+    def _split_into_days(a, b):
+        while a.date() != b.date():
+            next_day = a.date() + timedelta(days=1)
+            yield a.date(), next_day - a
+            a = next_day
+        yield b.date(), b - a
 
     @staticmethod
-    def _split_into_hours(time_from, time_to):
-        while time_from.date() != time_to.date() or time_from.hour != time_to.hour:
-            next_hour = time_from.replace(minute=0, second=0) + timedelta(hours=1)
-            yield time_from.hour, next_hour - time_from
-            time_from = next_hour
-        yield time_to.hour, time_to - time_from
+    def _split_into_hours(a, b):
+        while a.date() != b.date() or a.hour != b.hour:
+            next_hour = a.replace(minute=0, second=0) + timedelta(hours=1)
+            yield a.hour, next_hour - a
+            a = next_hour
+        yield b.hour, b - a
 
     def _process_database_record(self, record):
         return self._close_user_session(record.to_user())
diff --git a/vk/tracking/status_tracker.py b/vk/tracking/status_tracker.py
index d52af6a..d47de39 100644
--- a/vk/tracking/status_tracker.py
+++ b/vk/tracking/status_tracker.py
@@ -27,21 +27,21 @@ class StatusTracker:
         self.add_status_update_handler(writer.on_status_update)
         self.add_connection_error_handler(writer.on_connection_error)
 
-    def add_initial_status_handler(self, handler):
-        self._assert_is_callback(handler)
-        self._on_initial_status.append(handler)
+    def add_initial_status_handler(self, fn):
+        self._assert_is_callback(fn)
+        self._on_initial_status.append(fn)
 
-    def add_status_update_handler(self, handler):
-        self._assert_is_callback(handler)
-        self._on_status_update.append(handler)
+    def add_status_update_handler(self, fn):
+        self._assert_is_callback(fn)
+        self._on_status_update.append(fn)
 
-    def add_connection_error_handler(self, handler):
-        self._assert_is_callback(handler)
-        self._on_connection_error.append(handler)
+    def add_connection_error_handler(self, fn):
+        self._assert_is_callback(fn)
+        self._on_connection_error.append(fn)
 
     @staticmethod
-    def _assert_is_callback(handler):
-        if not isinstance(handler, Callable):
+    def _assert_is_callback(fn):
+        if not isinstance(fn, Callable):
             raise TypeError()
 
     _USER_FIELDS = UserField.DOMAIN, UserField.ONLINE, UserField.LAST_SEEN,
@@ -50,16 +50,16 @@ class StatusTracker:
         return {user.get_uid(): user for user in self._api.users_get(uids, self._USER_FIELDS)}
 
     def _notify_status(self, user):
-        for handler in self._on_initial_status:
-            handler(user)
+        for fn in self._on_initial_status:
+            fn(user)
 
     def _notify_status_update(self, user):
-        for handler in self._on_status_update:
-            handler(user)
+        for fn in self._on_status_update:
+            fn(user)
 
     def _notify_connection_error(self, e):
-        for handler in self._on_connection_error:
-            handler(e)
+        for fn in self._on_connection_error:
+            fn(e)
 
     def _query_initial_status(self, uids):
         while True:
diff --git a/vk/user.py b/vk/user.py
index 6fae83d..f63f793 100644
--- a/vk/user.py
+++ b/vk/user.py
@@ -9,30 +9,30 @@ from enum import Enum
 
 from .last_seen import LastSeen
 
-def _parse_last_seen(src):
-    if isinstance(src, LastSeen):
-        return src
-    elif isinstance(src, Mapping):
-        return LastSeen.from_api_response(src)
+def _parse_last_seen(x):
+    if isinstance(x, LastSeen):
+        return x
+    elif isinstance(x, Mapping):
+        return LastSeen.from_api_response(x)
     else:
         raise TypeError()
 
-def _parse_bool(src):
-    if isinstance(src, str):
-        if str(True) == src:
+def _parse_bool(x):
+    if isinstance(x, str):
+        if str(True) == x:
             return True
-        elif str(False) == src:
+        elif str(False) == x:
             return False
         else:
             raise ValueError()
     else:
-        return bool(src)
+        return bool(x)
 
-def _parse_hidden(src):
-    return _parse_bool(src)
+def _parse_hidden(x):
+    return _parse_bool(x)
 
-def _parse_online_flag(src):
-    return _parse_bool(src)
+def _parse_online_flag(x):
+    return _parse_bool(x)
 
 class UserField(Enum):
     UID = 'uid'
@@ -56,8 +56,8 @@ class DeactivationReason(Enum):
     def __str__(self):
         return self.value
 
-def _parse_deactivated(src):
-    return DeactivationReason(src)
+def _parse_deactivated(s):
+    return DeactivationReason(s)
 
 class User(Hashable, MutableMapping):
     @staticmethod