'Get LeftHand extra_specs (valid_keys only).'

def _get_lh_extra_specs(self, extra_specs, valid_keys):

    extra_specs_of_interest = {}
    for (key, value) in extra_specs.items():
        if (key in valid_keys):
            prefix = key.split(':')
            if (prefix[0] == 'hplh'):
                LOG.warning("The    'hplh'    prefix    is    deprecated.    Use    'hpelh'    instead.")
            extra_specs_of_interest[key] = value
    return extra_specs_of_interest
