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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 ensure_fixed_length_bytes(var):
 """Ensure that a variable with vlen bytes is converted to fixed width."""

    dims, data, attrs, encoding = unpack_for_encoding(var)
    if check_vlen_dtype(data.dtype) == bytes:
        # TODO: figure out how to handle this with dask
        data = np.asarray(data, dtype=np.string_)
    return Variable(dims, data, attrs, encoding)