A dictionary of the standard and non-standard CF attributes.
Note that modifying the returned dictionary will not change the attributes.
Examples
>>> f.attributes
{'Conventions': 'CF-1.0',
'_FillValue': 1e+20,
'cell_methods': <CF CellMethods: time: mean>,
'experiment_id': 'stabilization experiment (SRES A1B)',
'long_name': 'Surface Air Temperature',
'standard_name': 'AIR_TEMP',
'title': 'SRES A1B',
'units': 'K'}