code: private Boolean getGlobalParam(Map property) {
  		Boolean global = null;
  		Object globalObj = property.get("global");
  		if (globalObj == null) {
  			// default behaviour before liquibase 3.4
  			global = true;
  		} else {
  			global = (Boolean) globalObj;
  		}
  		return global;
  	}
docs: Extract the global parameter from the properties.
  
  @param property the map of props
  @return the global param