✨ feat(base.py): add methods to get, update, and upsert fields in the Template class for easier field manipulation

🔧 chore(base.py): refactor Template class to improve code readability and maintainability

src/backend/langflow/template/template/base.py

@@ -1,8 +1,9 @@
 from typing import Callable, Union
 
+from pydantic import BaseModel, model_serializer
+
 from langflow.template.field.base import TemplateField
 from langflow.utils.constants import DIRECT_TYPES
-from pydantic import BaseModel, model_serializer
 
 
 class Template(BaseModel):
@@ -39,3 +40,25 @@ class Template(BaseModel):
 
     def add_field(self, field: TemplateField) -> None:
         self.fields.append(field)
+
+    def get_field(self, field_name: str) -> TemplateField:
+        """Returns the field with the given name."""
+        field = next((field for field in self.fields if field.name == field_name), None)
+        if field is None:
+            raise ValueError(f"Field {field_name} not found in template {self.type_name}")
+        return field
+
+    def update_field(self, field_name: str, field: TemplateField) -> None:
+        """Updates the field with the given name."""
+        for idx, template_field in enumerate(self.fields):
+            if template_field.name == field_name:
+                self.fields[idx] = field
+                return
+        raise ValueError(f"Field {field_name} not found in template {self.type_name}")
+
+    def upsert_field(self, field_name: str, field: TemplateField) -> None:
+        """Updates the field with the given name or adds it if it doesn't exist."""
+        try:
+            self.update_field(field_name, field)
+        except ValueError:
+            self.add_field(field)