<StructureDefinition xmlns="http://hl7.org/fhir">
  <url value="https://example.org/fhir/StructureDefinition/MyAddress" />
  <name value="MyAddress" />
  <status value="draft" />
  <description value="Example profile of Address" />
  <fhirVersion value="4.0.1" />
  <kind value="complex-type" />
  <abstract value="false" />
  <type value="Address" />
  <baseDefinition value="http://hl7.org/fhir/StructureDefinition/Address" />
  <derivation value="constraint" />
  <differential>
    <element id="Address">
      <path value="Address" />
      <constraint>
        <key value="Demo-1" />
        <requirements value="Something" />
        <severity value="error" />
        <human value="Example Error message" />
        <expression value="line.empty() or $this.hasValue()" />
      </constraint>
    </element>
  </differential>
</StructureDefinition>