Query: What was the result of my last blood test for Creatinine?, FHIR Resource: {'resourceType': 'Observation', 'status': 'final', 'category': [{'coding': [{'system': 'http://terminology.hl7.org/CodeSystem/observation-category', 'code': 'laboratory', 'display': 'Laboratory'}]}], 'code': {'coding': [{'system': 'http://loinc.org', 'code': '5803-2', 'display': 'pH of Urine by Test strip'}], 'text': 'pH of Urine by Test strip'}, 'subject': {'reference': 'urn:uuid:fe5ede7c-a259-11a8-bb0e-26c3c8415ce6'}, 'effectiveDateTime': '2023-11-19T23:29:38+05:30', 'valueQuantity': {'value': 5.2751, 'unit': 'pH', 'system': 'http://unitsofmeasure.org', 'code': 'pH'}, 'interpretation': None}