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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 savenetcdf(dataarray, filename=None):
 """Save a dataarray to a NetCDF file. Args: dataarray (xarray.DataArray):
 Dataarray to be saved. filename (str):
 Filename (used as <filename>.nc). If not spacified, random 8-character name will be used. """

    if filename is None:
        if dataarray.name is not None:
            filename = dataarray.name
        else:
            filename = uuid4().hex[:8]
    else:
        filename = str(Path(filename).expanduser())

    if not filename.endswith('.nc'):
        filename += '.nc'

    dataarray.to_netcdf(filename)
    logger.info('{} has been created.'.format(filename))