feat: implemented _str_ and _repr_ methods for python schema classes (#1095)

* feat: implemented _str_ and _repr_ methods for python schema classes

* fix: improve string formatting in BasicValueType and TableType classes

* fix: remove UTable from TABLE_TYPES and update TableType class to reflect changes

Author: shresthashim

python/cocoindex/typing.py

@@ -516,6 +516,13 @@ class VectorTypeSchema:
     element_type: "BasicValueType"
     dimension: int | None
 
+    def __str__(self) -> str:
+        dimension_str = f", {self.dimension}" if self.dimension is not None else ""
+        return f"Vector[{self.element_type}{dimension_str}]"
+
+    def __repr__(self) -> str:
+        return self.__str__()
+
     @staticmethod
     def decode(obj: dict[str, Any]) -> "VectorTypeSchema":
         return VectorTypeSchema(
@@ -534,6 +541,13 @@ def encode(self) -> dict[str, Any]:
 class UnionTypeSchema:
     variants: list["BasicValueType"]
 
+    def __str__(self) -> str:
+        types_str = " | ".join(str(t) for t in self.variants)
+        return f"Union[{types_str}]"
+
+    def __repr__(self) -> str:
+        return self.__str__()
+
     @staticmethod
     def decode(obj: dict[str, Any]) -> "UnionTypeSchema":
         return UnionTypeSchema(
@@ -573,6 +587,23 @@ class BasicValueType:
     vector: VectorTypeSchema | None = None
     union: UnionTypeSchema | None = None
 
+    def __str__(self) -> str:
+        if self.kind == "Vector" and self.vector is not None:
+            dimension_str = (
+                f", {self.vector.dimension}"
+                if self.vector.dimension is not None
+                else ""
+            )
+            return f"Vector[{self.vector.element_type}{dimension_str}]"
+        elif self.kind == "Union" and self.union is not None:
+            types_str = " | ".join(str(t) for t in self.union.variants)
+            return f"Union[{types_str}]"
+        else:
+            return self.kind
+
+    def __repr__(self) -> str:
+        return self.__str__()
+
     @staticmethod
     def decode(obj: dict[str, Any]) -> "BasicValueType":
         kind = obj["kind"]
@@ -603,6 +634,18 @@ class EnrichedValueType:
     nullable: bool = False
     attrs: dict[str, Any] | None = None
 
+    def __str__(self) -> str:
+        result = str(self.type)
+        if self.nullable:
+            result += "?"
+        if self.attrs:
+            attrs_str = ", ".join(f"{k}: {v}" for k, v in self.attrs.items())
+            result += f" [{attrs_str}]"
+        return result
+
+    def __repr__(self) -> str:
+        return self.__str__()
+
     @staticmethod
     def decode(obj: dict[str, Any]) -> "EnrichedValueType":
         return EnrichedValueType(
@@ -625,6 +668,12 @@ class FieldSchema:
     name: str
     value_type: EnrichedValueType
 
+    def __str__(self) -> str:
+        return f"{self.name}: {self.value_type}"
+
+    def __repr__(self) -> str:
+        return self.__str__()
+
     @staticmethod
     def decode(obj: dict[str, Any]) -> "FieldSchema":
         return FieldSchema(name=obj["name"], value_type=EnrichedValueType.decode(obj))
@@ -640,6 +689,13 @@ class StructSchema:
     fields: list[FieldSchema]
     description: str | None = None
 
+    def __str__(self) -> str:
+        fields_str = ", ".join(str(field) for field in self.fields)
+        return f"Struct({fields_str})"
+
+    def __repr__(self) -> str:
+        return self.__str__()
+
     @classmethod
     def decode(cls, obj: dict[str, Any]) -> Self:
         return cls(
@@ -658,6 +714,13 @@ def encode(self) -> dict[str, Any]:
 class StructType(StructSchema):
     kind: Literal["Struct"] = "Struct"
 
+    def __str__(self) -> str:
+        # Use the parent's __str__ method for consistency
+        return super().__str__()
+
+    def __repr__(self) -> str:
+        return self.__str__()
+
     def encode(self) -> dict[str, Any]:
         result = super().encode()
         result["kind"] = self.kind
@@ -670,6 +733,18 @@ class TableType:
     row: StructSchema
     num_key_parts: int | None = None  # Only for KTable
 
+    def __str__(self) -> str:
+        if self.kind == "KTable":
+            num_parts = self.num_key_parts if self.num_key_parts is not None else 1
+            table_kind = f"KTable({num_parts})"
+        else:  # LTable
+            table_kind = "LTable"
+
+        return f"{table_kind}({self.row})"
+
+    def __repr__(self) -> str:
+        return self.__str__()
+
     @staticmethod
     def decode(obj: dict[str, Any]) -> "TableType":
         row_obj = obj["row"]