did the needful

svm_prefilter_service/schemas/__init__.py

@@ -1 +1,2 @@
 #!/usr/bin/env python3
+from .sample_schema import SampleSchema

svm_prefilter_service/schemas/sample_schema.py

@@ -0,0 +1,7 @@
+#!/usr/bin/env python3
+from marshmallow import fields, Schema
+
+
+class SampleSchema(Schema):
+    date = fields.DateTime(required=True)
+    device_id = fields.Integer(required=True)