postgresDB operation with python

below code describes how to check if 'table' is exist in database or not using pg package. dirty code ... :-(

import pg
import sys

def is_table_exist1(dbobj, table):
    """ return True if table is exist in database """
    print "is_table_exist1 called"
    try:
        for i in dbobj.get_tables():
            if i == table:
                return True
    except IndexError, (errno):
        print "%s" %(errno)
        return False
    return False

def is_table_exist2(dbobj, table):
    """ return True if table is exist in database """
    print "is_table_exist2 called"
    try:
        print dbobj.get_attnames(table)
        return True
    except pg.ProgrammingError, (errno):
        print "%s" %(errno)
        return False

def main():
    # set default hostname                                                      
    pg.set_defhost('localhost')
    defhost = pg.get_defhost()

    # set default port number                                                   
    pg.set_defport(5432)
    defport = pg.get_defport()

    # set default database                                                      
    pg.set_defbase('testdb')
    defbase = pg.get_defbase()

    # initialize pg.DB object                                                   
    mydb = pg.DB(user='postgres', passwd='postgres')

    # print names of all databases                                              
    dblist = mydb.get_databases()

    # check if table is exist in database                                       
    if is_table_exist1(mydb, 'public.foo') == False:
        mydb.close()
        sys.exit(1)

    # check if table is exist in database                                       
    if is_table_exist2(mydb, 'public.foo') == False:
        mydb.close()
        sys.exit(1)

    for r in mydb.query(
        "SELECT v1, v2, v3, v4 FROM %s" % ('public.foo')
        ).dictresult():
        print '%(v1)s %(v2)s %(v3)s %(v4)s' % r

    #close dbobj                                                                
    mydb.close()

if __name__ == "__main__":
    main()