count number of unique alphabets in each string
for k in range ( len ( na [ j ] ) ) : NEW_LINE INDENT x = ord ( na [ j ] [ k ] ) - ord ( ' A ' ) NEW_LINE if ( ( na [ j ] [ k ] != ' ▁ ' ) and ( character [ x ] == False ) ) : NEW_LINE INDENT c [ j ] += 1 NEW_LINE character [ x ] = True NEW_LINE DEDENT DEDENT