code: func flattenMultiMaps(m map[string]interface{}) error {
  	for k, v := range m {
  		switch v := v.(type) {
  		case []map[string]interface{}:
  			switch {
  			case len(v) > 1:
  				return fmt.Errorf("multiple map declarations not supported for variables")
  			case len(v) == 1:
  				m[k] = v[0]
  			}
  		}
  	}
  	return nil
  }
docs: // Variables don't support any type that can be configured via multiple
  // declarations of the same HCL map, so any instances of
  // []map[string]interface{} are either a single map that can be flattened, or
  // are invalid config.