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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 export_csv(ekey, dstore):
 """ Default csv exporter for arrays stored in the output.hdf5 file :param ekey: export key :param dstore: datastore object :returns: a list with the path of the exported file """

    name = ekey[0] + '.csv'
    try:
        array = dstore[ekey[0]].value
    except AttributeError:
        # this happens if the key correspond to a HDF5 group
        return []  # write a custom exporter in this case
    if len(array.shape) == 1:  # vector
        array = array.reshape((len(array), 1))
    return [write_csv(dstore.export_path(name), array)]