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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 dataSetMissingValue(h5Dataset):
 """ Returns the missingData given a HDF-5 dataset Looks for one of the following attributes: _FillValue, missing_value, MissingValue, missingValue. Returns None if these attributes are not found. HDF-EOS and NetCDF files seem to put the attributes in 1-element arrays. So if the attribute contains an array of one element, that first element is returned here. """

    attributes = h5Dataset.attrs
    if not attributes:
        return None # a premature optimization :-)

    for key in ('missing_value', 'MissingValue', 'missingValue', 'FillValue', '_FillValue'):
        if key in attributes:
            missingDataValue = attributes[key]
            if is_an_array(missingDataValue) and len(missingDataValue) == 1:
                return missingDataValue[0] # In case of HDF-EOS and NetCDF files
            else:
                return missingDataValue
    return None