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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 uyirmei_constructed( mei_idx, uyir_idx):
 """ construct uyirmei letter give mei index and uyir index """

    idx,idy = mei_idx,uyir_idx
    assert ( idy >= 0 and idy < uyir_len() )
    assert ( idx >= 0 and idx < 6+mei_len() )
    return grantha_agaram_letters[mei_idx]+accent_symbols[uyir_idx]