'Check whether the SSC data for a FlexVol matches extra specs.
A set of extra specs is considered a match for a FlexVol if, for each
extra spec, the value matches what is in SSC or the key is unknown to
SSC.'

def _flexvol_matches_extra_specs(self, flexvol_info, extra_specs):

    for (extra_spec_key, extra_spec_value) in extra_specs.items():
        if (extra_spec_key in flexvol_info):
            if (not self._extra_spec_matches(extra_spec_value, flexvol_info[extra_spec_key])):
                return False
    return True
