code: public SnapshotInner update(String resourceGroupName, String snapshotName, SnapshotUpdate snapshot) {
          return updateWithServiceResponseAsync(resourceGroupName, snapshotName, snapshot).toBlocking().last().body();
      }
docs: Updates (patches) a snapshot.
  
  @param resourceGroupName The name of the resource group.
  @param snapshotName The name of the snapshot that is being created. The name can't be changed after the snapshot is created. Supported characters for the name are a-z, A-Z, 0-9 and _. The max name length is 80 characters.
  @param snapshot Snapshot object supplied in the body of the Patch snapshot operation.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @throws CloudException thrown if the request is rejected by server
  @throws RuntimeException all other wrapped checked exceptions if the request fails to be sent
  @return the SnapshotInner object if successful.