code: def _validate_all(data, schema):
      
      vldtr = jsonschema.Draft4Validator(schema)  # :raises: SchemaError, ...
      errors = list(vldtr.iter_errors(data))
  
      return (not errors, [err.message for err in errors])
docs: See the descritpion of :func:`validate` for more details of parameters and
      return value.
  
      :seealso: https://python-jsonschema.readthedocs.io/en/latest/validate/,
      a section of 'iter_errors' especially