Move unit system to util (#2763)

homeassistant/helpers/typing.py

@@ -8,22 +8,9 @@ try:
 except ImportError:
     NewType = None
 
-# HACK: mypy/pytype will import, other interpreters will not; this is to avoid
-#       circular dependencies where the type is needed.
-#       All homeassistant types should be imported this way.
-#       Documentation
-#       http://mypy.readthedocs.io/en/latest/common_issues.html#import-cycles
-# pylint: disable=using-constant-test,unused-import
-if False:
-    from homeassistant.core import HomeAssistant  # NOQA
-    from homeassistant.helpers.unit_system import UnitSystem  # NOQA
-# ENDHACK
-
 # pylint: disable=invalid-name
 if NewType:
     ConfigType = NewType('ConfigType', Dict[str, Any])
-    HomeAssistantType = NewType('HomeAssistantType', 'HomeAssistant')
-    UnitSystemType = NewType('UnitSystemType', 'UnitSystem')
 
     # Custom type for recorder Queries
     QueryType = NewType('QueryType', Any)
@@ -32,8 +19,6 @@ if NewType:
 # pylint: disable=invalid-name
 else:
     ConfigType = Dict[str, Any]  # type: ignore
-    HomeAssistantType = 'HomeAssistant'  # type: ignore
-    UnitSystemType = 'UnitSystemType'  # type: ignore
 
     # Custom type for recorder Queries
     QueryType = Any  # type: ignore