'Adjust extra spec values for simple comparison to SSC values.
Most extra-spec key-value tuples may be directly compared. But the
boolean values that take the form \'<is> True\' or \'<is> False\' must be
modified to allow comparison with the values we keep in the SSC and
report to the scheduler.'

def _modify_extra_specs_for_comparison(self, extra_specs):

    modified_extra_specs = copy.deepcopy(extra_specs)
    for (key, value) in extra_specs.items():
        if isinstance(value, six.string_types):
            if re.match('<is>\\s+True', value, re.I):
                modified_extra_specs[key] = True
            elif re.match('<is>\\s+False', value, re.I):
                modified_extra_specs[key] = False
    return modified_extra_specs
