def Dice_coeff(wordA,wordB):
    """
        # Calculate edit-distance - Implements the Dice coefficent
        # Ref: https://en.wikipedia.org/wiki/S%C3%B8rensen%E2%80%93Dice_coefficient
        # distance should be between 0 - 1.0. can be used as a similarity match
    """
    if not type(wordA) is list:
        lettersA = tamil.utf8.get_letters(wordA)
    else:
        lettersA = wordA
    
    if not type(wordB) is list:
        lettersB = tamil.utf8.get_letters(wordB)
    else:
        lettersB = wordB
    n_A = len(lettersA)
    n_B = len(lettersB)
    # OK only if unique - set(lettersA).intersection(set(lettersB))
    n_AB = len( list( filter( lambda cmnL: cmnL in lettersB, lettersA) ) )
    return (2.0*n_AB)/(n_A+n_B)