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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def compare_words_lexicographic( word_a, word_b ):
 """ compare words in Tamil lexicographic order """

    # sanity check for words to be all Tamil
    if ( not all_tamil(word_a) ) or (not all_tamil(word_b)) :
        #print("## ")
        #print(word_a)
        #print(word_b)
        #print("Both operands need to be Tamil words")
        pass
    La = len(word_a)
    Lb = len(word_b)
    all_TA_letters = u"".join(tamil_letters)
    for itr in range(0,min(La,Lb)):
            pos1 = all_TA_letters.find( word_a[itr] )
            pos2 = all_TA_letters.find( word_b[itr] )

            if pos1 != pos2 :
                    #print  not( pos1 > pos2), pos1, pos2
                    return cmp(pos1, pos2)

    # result depends on if La is shorter than Lb, or 0 if La == Lb  i.e. cmp
    return cmp(La,Lb)