It's not obvious how to turn authentication off after using it, so
I recommend using custom handles with authentication.
Usage
authenticate(user, password, type = "basic")
Arguments
user
user name
password
password
type
type of HTTP authentication. Should be one of the following
types supported by Curl: basic, digest, digest_ie, gssnegotiate,
ntlm, any. It defaults to "basic", the most common type.