Query: What is my current body mass index (BMI)?, 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': '2947-0', 'display': 'Sodium [Moles/volume] in Blood'}], 'text': 'Sodium [Moles/volume] in Blood'}, 'subject': {'reference': 'urn:uuid:57d7bafe-dd9a-5d19-847c-a6743f31a3ee'}, 'effectiveDateTime': '2019-07-07T23:25:17+05:30', 'valueQuantity': {'value': 138.76, 'unit': 'mmol/L', 'system': 'http://unitsofmeasure.org', 'code': 'mmol/L'}, 'interpretation': None}