Some typing related fixes (home-assistant#15899)

* Fix FlowManager.async_init handler type

It's not a Callable, but typically a key pointing to one in a dict.

* Mark pip_kwargs return type hint as Any-valued dict

install_package takes other than str args too.

homeassistant/data_entry_flow.py

@@ -2,7 +2,7 @@
 import logging
 import uuid
 import voluptuous as vol
-from typing import Dict, Any, Callable, List, Optional  # noqa pylint: disable=unused-import
+from typing import Dict, Any, Callable, Hashable, List, Optional  # noqa pylint: disable=unused-import
 from .core import callback, HomeAssistant
 from .exceptions import HomeAssistantError
 
@@ -49,7 +49,7 @@ def async_progress(self) -> List[Dict]:
             'source': flow.source,
         } for flow in self._progress.values()]
 
-    async def async_init(self, handler: Callable, *, context: Dict = None,
+    async def async_init(self, handler: Hashable, *, context: Dict = None,
                          data: Any = None) -> Any:
         """Start a configuration flow."""
         flow = await self._async_create_flow(

homeassistant/requirements.py

@@ -3,7 +3,7 @@
 from functools import partial
 import logging
 import os
-from typing import List, Dict, Optional
+from typing import Any, Dict, List, Optional
 
 import homeassistant.util.package as pkg_util
 from homeassistant.core import HomeAssistant
@@ -37,7 +37,7 @@ async def async_process_requirements(hass: HomeAssistant, name: str,
     return True
 
 
-def pip_kwargs(config_dir: Optional[str]) -> Dict[str, str]:
+def pip_kwargs(config_dir: Optional[str]) -> Dict[str, Any]:
     """Return keyword arguments for PIP install."""
     kwargs = {
         'constraints': os.path.join(os.path.dirname(__file__), CONSTRAINT_FILE)