Refactor cast function in utils.py (#1340)

- less indentation, more readable code
- early return

plexapi/utils.py

@@ -144,22 +144,21 @@ def cast(func, value):
             func (func): Callback function to used cast to type (int, bool, float).
             value (any): value to be cast and returned.
     """
-    if value is not None:
+    if value is None:
+        return value
     if func == bool:
         if value in (1, True, "1", "true"):
             return True
-            elif value in (0, False, "0", "false"):
+        if value in (0, False, "0", "false"):
             return False
-            else:
         raise ValueError(value)
 
-        elif func in (int, float):
+    if func in (int, float):
         try:
             return func(value)
         except ValueError:
             return float('nan')
     return func(value)
-    return value
 
 
 def joinArgs(args):