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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 is_arabicword(word):
 """ Checks for an valid Arabic word. An Arabic word not contains spaces, digits and pounctuation avoid some spelling error, TEH_MARBUTA must be at the end. @param word: input word @type word: unicode @return: True if all charaters are in Arabic block @rtype: Boolean """

    if len(word) == 0:
        return False
    elif re.search(u"([^\u0600-\u0652%s%s%s])" \
                           % (LAM_ALEF, LAM_ALEF_HAMZA_ABOVE, LAM_ALEF_MADDA_ABOVE), word):
        return False
    elif is_haraka(word[0]) or word[0] in (WAW_HAMZA, YEH_HAMZA):
        return False
    # if Teh Marbuta or Alef_Maksura not in the end
    elif re.match(u"^(.)*[%s](.)+$" % ALEF_MAKSURA, word):
        return False
    elif re.match(u"^(.)*[%s]([^%s%s%s])(.)+$" % \
                          (TEH_MARBUTA, DAMMA, KASRA, FATHA), word):
        return False
    else:
        return True