def savefile(self,filepath=''):
        
        if self.isempty(): raise Exception('Empty table')
        #open a file
        fn=os.path.join(filepath,self.get_name()+'.xls')
        f=open(fn,'w')
        
        f.write(self.to_xls())
        
        #close the file
        f.close()
Converts a dictionary to a tuple that can be used as an immutable key.
dataset/ETHPy150Open taoliu/taolib/Assoc/tables.py/Table.savefile--crossover with--dataset/ETHPy150Open google/oauth2client/oauth2client/contrib/multistore_file.py/_dict_to_tuple_key