code: public DbxClientV2 asAdmin(String adminId) {
          if (adminId == null) {
              throw new IllegalArgumentException("'adminId' should not be null");
          }
  
          DbxRawClientV2 asAdminClient = new DbxTeamRawClientV2(
              _client.getRequestConfig(),
              credential,
              _client.getHost(),
              _client.getUserId(),
              null,
              adminId,
              null
          );
          return new DbxClientV2(asAdminClient);
      }
docs: Returns a {@link DbxClientV2} that performs requests against Dropbox API
  user endpoints as the given team admin.
  
  <p> This method performs no validation of the team admin ID. </p>
  
  @param adminId  Team member ID of the admin in client's team, never
  {@code null}.
  
  @return Dropbox client that issues requests to user endpoints as the
  given team Admin.
  
  @throws IllegalArgumentException  If {@code adminId} is {@code null}