add serializable

dedocutils/data_structures/bbox.py

@@ -5,9 +5,11 @@
 
 import numpy as np
 
+from dedocutils.data_structures.serializable import Serializable
+
 
 @dataclass
-class BBox:
+class BBox(Serializable):
     """
     Bounding box around some page object, the coordinate system starts from top left corner.
     """

dedocutils/data_structures/serializable.py

@@ -0,0 +1,16 @@
+from abc import ABC, abstractmethod
+
+
+class Serializable(ABC):
+    """
+    Base class for the serializable objects which we need convert to dict.
+    """
+    @abstractmethod
+    def to_dict(self) -> dict:
+        """
+        Convert class data into dictionary representation.
+        Dictionary key should be string and dictionary value should be json serializable.
+
+        :return: dict with all class data.
+        """
+        pass