* ``append_const`` [required: ``const``; relevant: :attr:`dest`]
Like ``store_const``, but the value ``const`` is appended to :attr:`dest`; as
- with ``append``, :attr:`dest` defaults to ``None``, and an an empty list is
+ with ``append``, :attr:`dest` defaults to ``None``, and an empty list is
automatically created the first time the option is encountered.
* ``count`` [relevant: :attr:`dest`]
* if the number starts with ``0``, it is parsed as an octal number
-* if the number starts with ``0b``, is is parsed as a binary number
+* if the number starts with ``0b``, it is parsed as a binary number
* otherwise, the number is parsed as a decimal number