args: Remove implied default=False

> 'store_true' and 'store_false' - These are special cases of
> 'store_const' used for storing the values True and False
> respectively. In addition, they create default values of
> False and True respectively.

https://docs.python.org/3/library/argparse.html#argparse.ArgumentParser.add_argument

nixops/args.py

@@ -355,7 +355,6 @@
 subparser.add_argument(
  "--now",
  dest="now",
- default=False,
  action="store_true",
  help="do not acquire a lock before fetching the state",
 )
@@ -450,14 +449,12 @@
  "--freeze",
  dest="freeze_fs",
  action="store_true",
- default=False,
  help="freeze filesystems for non-root filesystems that support this (e.g. xfs)",
 )
 subparser.add_argument(
  "--force",
  dest="force",
  action="store_true",
- default=False,
  help="start new backup even if previous is still running",
 )
 subparser.add_argument(
@@ -485,17 +482,12 @@
  help="do not perform backup actions on the specified machines",
 )
 subparser.add_argument(
- "--wait",
- dest="wait",
- action="store_true",
- default=False,
- help="wait until backup is finished",
+ "--wait", dest="wait", action="store_true", help="wait until backup is finished",
 )
 subparser.add_argument(
  "--latest",
  dest="latest",
  action="store_true",
- default=False,
  help="show status of latest backup only",
 )
 
@@ -505,7 +497,6 @@
 subparser.add_argument(
  "--keep-physical",
  dest="keep_physical",
- default=False,
  action="store_true",
  help="do not remove the physical backups, only remove backups from nixops state",
 )
@@ -525,7 +516,6 @@
 subparser.add_argument(
  "--keep-physical",
  dest="keep_physical",
- default=False,
  action="store_true",
  help="do not remove the physical backups, only remove backups from nixops state",
 )