add __repr__ method to FieldType

Author: andreax79

cstruct/field.py

@@ -220,3 +220,6 @@ def align_filed_offset(self) -> None:
     def copy(self) -> "FieldType":
         "Return a shallow copy of this FieldType"
         return copy.copy(self)
+
+    def __repr__(self) -> str:  # pragma: no cover
+        return repr(self.__dict__)