Move imports to top for pushetta (#29332)

* Move imports to top for pushetta

* Make Pushetta.exceptions import lowercase and snakecase

homeassistant/components/pushetta/notify.py

@@ -1,17 +1,17 @@
 """Pushetta platform for notify component."""
 import logging
 
+from pushetta import Pushetta, exceptions as pushetta_exceptions
 import voluptuous as vol
 
-from homeassistant.const import CONF_API_KEY
-import homeassistant.helpers.config_validation as cv
-
 from homeassistant.components.notify import (
     ATTR_TITLE,
     ATTR_TITLE_DEFAULT,
     PLATFORM_SCHEMA,
     BaseNotificationService,
 )
+from homeassistant.const import CONF_API_KEY
+import homeassistant.helpers.config_validation as cv
 
 _LOGGER = logging.getLogger(__name__)
 
@@ -44,7 +44,6 @@ class PushettaNotificationService(BaseNotificationService):
 
     def __init__(self, api_key, channel_name, send_test_msg):
         """Initialize the service."""
-        from pushetta import Pushetta
 
         self._api_key = api_key
         self._channel_name = channel_name
@@ -56,15 +55,14 @@ class PushettaNotificationService(BaseNotificationService):
 
     def send_message(self, message="", **kwargs):
         """Send a message to a user."""
-        from pushetta import exceptions
 
         title = kwargs.get(ATTR_TITLE, ATTR_TITLE_DEFAULT)
 
         try:
             self.pushetta.pushMessage(self._channel_name, f"{title} {message}")
-        except exceptions.TokenValidationError:
+        except pushetta_exceptions.TokenValidationError:
             _LOGGER.error("Please check your access token")
             self.is_valid = False
-        except exceptions.ChannelNotFoundError:
+        except pushetta_exceptions.ChannelNotFoundError:
             _LOGGER.error("Channel '%s' not found", self._channel_name)
             self.is_valid = False