Add option_was_set function

certbot/cli.py

@@ -217,6 +217,21 @@ def set_by_cli(var):
 set_by_cli.detector = None
 
 
+def option_was_set(option, value):
+    """Was option set by the user or does it differ from the default?
+
+    :param str option: configuration variable being considered
+    :param value: value of the configuration variable named option
+
+    :returns: True if the option was set, otherwise, False
+    :rtype: bool
+
+    """
+    return (set_by_cli(option) or
+            option not in DEFAULTS or
+            DEFAULTS[option] != value)
+
+
 def argparse_type(variable):
     "Return our argparse type function for a config variable (default: str)"
     # pylint: disable=protected-access