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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 equities(country='US'):
 """ Return a DataFrame of current US equities. .. versionadded:: 0.4.0 .. versionchanged:: 0.5.0 Return a DataFrame Parameters country : str, optional Country code for equities to return, defaults to 'US'. Returns ------- eqs : :class:`pandas.DataFrame` DataFrame whose index is a list of all current ticker symbols. Columns are 'Security Name' (e.g. 'Zynerba Pharmaceuticals, Inc. - Common Stock') and 'Exchange' ('NASDAQ', 'NYSE', 'NYSE MKT', etc.) Examples -------- Notes ----- Currently only US markets are supported. """

    nasdaqblob, otherblob = _getrawdata()
    eq_triples = []
    eq_triples.extend(_get_nas_triples(nasdaqblob))
    eq_triples.extend(_get_other_triples(otherblob))
    eq_triples.sort()
    index = [triple[0] for triple in eq_triples]
    data = [triple[1:] for triple in eq_triples]
    return pd.DataFrame(data, index, columns=['Security Name', 'Exchange'], dtype=str)