code: def namedb_open( path ):
      
      con = sqlite3.connect( path, isolation_level=None, timeout=2**30 )
      db_query_execute(con, 'pragma mmap_size=536870912', ())
      con.row_factory = namedb_row_factory
  
      version = namedb_get_version(con)
      if not semver_equal(version, VERSION):
          # wrong version
          raise Exception('Database has version {}, but this node is version {}.  Please update your node database (such as with fast_sync).'.format(version, VERSION))
  
      return con
docs: Open a connection to our database