Converting SDF to CSV using loop

from os import listdir
from rdkit import chem
from rdkit.Chem.ChemUtilsSDFToCSV import convert

with open (r'trial.csv', 'a') as csvfile:
    for i in listdir(path):#path => the path of the folder where all the sdf files are present

        if i[-1:-4:-1] == 'fds':
            Suppl = chem.SDMolSupplier(i)
            convert(Suppl, csvfile)