Creates a new Cookie with the given attributes.
domain starts with ".", that indicates a domain (which matches the string after the ".", or any hostname that has
as a suffix). Otherwise, it is a hostname and must match exactly.
max_age is used to set the "expires" attribute on the cookie; pass -1 to not include the attribute (indicating that the cookie
expires with the current session), 0 for an already-expired cookie, or a lifetime in seconds. You can use the constants
COOKIE_MAX_AGE_ONE_YEAR (or multiples thereof) to calculate this
value. (If you really care about setting the exact time that the cookie will expire, use
cookie domain or hostname
cookie path, or
max age of the cookie, or -1 for a session cookie
a new Cookie.