refactor(dfn): rename _SCALAR_TYPES to public SCALAR_TYPES (#236)

This variable is accessed externally (here), which means it should be a public variable, not private.

Keep a private _SCALAR_TYPES copy for now.

Author: mwtoews

modflow_devtools/dfn.py

@@ -115,7 +115,8 @@ def block_sort_key(item) -> int:
 ]
 
 
-_SCALAR_TYPES = ("keyword", "integer", "double precision", "string")
+SCALAR_TYPES = ("keyword", "integer", "double precision", "string")
+_SCALAR_TYPES = SCALAR_TYPES  # allow backwards compat; imported by flopy
 
 
 Dfns = dict[str, "Dfn"]
@@ -130,7 +131,7 @@ def get_blocks(dfn: "Dfn") -> Blocks:
     """
 
     def _is_block(item: tuple[str, Any]) -> bool:
-        k, v = item
+        k, _v = item
         return k not in Dfn.__annotations__
 
     return dict(
@@ -455,7 +456,7 @@ def _item() -> Field:
                         return _convert_field(next(iter(flat.getlist(item_names[0]))))
 
                     # implicit simple record (no children)
-                    if all(t in _SCALAR_TYPES for t in item_types):
+                    if all(t in SCALAR_TYPES for t in item_types):
                         return Field(
                             name=_name,
                             type="record",
@@ -543,7 +544,7 @@ def _fields() -> Fields:
                 # for now, we can tell a var is an array if its type
                 # is scalar and it has a shape. once we have proper
                 # typing, this can be read off the type itself.
-                elif shape is not None and _type not in _SCALAR_TYPES:
+                elif shape is not None and _type not in SCALAR_TYPES:
                     raise TypeError(f"Unsupported array type: {_type}")
 
                 else: