def u_students_extension(data)
      db_extensions = { "name"=>"u_students_extension", "recordFound"=>false,
                        "_field"=> [] }
      data.each do |key, value|
        db_extensions["_field"] << {"name"=>"#{key}", "type"=>"String", "value"=>"#{value}"}
      end
      db_extensions
    end
def u_students_extension(data)
      db_extensions = { "name"=>"u_students_extension", "recordFound"=>false,
                        "_field"=> [] }
      data.each do |key, value|
        db_extensions["_field"] << {"name"=>"#{key}", "type"=>"String", "value"=>"#{value}"}
      end
      db_extensions
    end
prepare data to update student database extensions
 @param data [Hash] - with the format: {u_students_extension: {field1: data1, field2: data2}}
 @return [Hash] - with data like below:
 { "name"=>"u_students_extension",
   "recordFound"=>false,
   "_field"=> [
     {"name"=>"preferredname", "type"=>"String", "value"=>"Joe"},
     {"name"=>"student_email", "type"=>"String", "value"=>"joe@las.ch"},
   ]
 }