docs: def createDAM(dam_name, config):
          ''' create DAM '''
          if 'yahoo' == dam_name:
              from analyzerdam.yahooDAM import YahooDAM
              dam=YahooDAM()
          elif 'google' == dam_name:
              from analyzerdam.google import GoogleDAM
              dam=GoogleDAM()
          elif 'excel' == dam_name:
              from analyzerdam.excelDAM import ExcelDAM
              dam=ExcelDAM()
          elif 'hbase' == dam_name:
              from analyzerdam.hbaseDAM import HBaseDAM
              dam=HBaseDAM()
          elif 'sql' == dam_name:
              from analyzerdam.sqlDAM import SqlDAM
              dam=SqlDAM(config)
          elif 'cex' == dam_name:
              from analyzerdam.cex import CexDAM
              dam=CexDAM(config)
          else:
              raise UfException(Errors.INVALID_DAM_TYPE,
                                "DAM type is invalid %s" % dam_name)
  
          return dam