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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 dataSetElementType(h5Dataset):
 """ Returns a string describing the element type of the dataset """

    dtype =  h5Dataset.dtype

    if dtype.names:
        return '<structured>'
    else:
        if dtype.metadata and 'vlen' in dtype.metadata:
            vlen_type = dtype.metadata['vlen']
            try:
                return "<vlen {}>".format(vlen_type.__name__)  # when vlen_type is a type
            except AttributeError: #
                return "<vlen {}>".format(vlen_type.name)      # when vlen_type is a dtype

    return str(dtype)