'This is the standard constructor for creating an association.
@param handle: This is the handle the server gave this
association.
@type handle: C{str}
@param secret: This is the shared secret the server generated
for this association.
@type secret: C{str}
@param issued: This is the time this association was issued,
in seconds since 00:00 GMT, January 1, 1970.  (ie, a unix
timestamp)
@type issued: C{int}
@param lifetime: This is the amount of time this association
is good for, measured in seconds since the association was
issued.
@type lifetime: C{int}
@param assoc_type: This is the type of association this
instance represents.  The only valid value of this field
at this time is C{\'HMAC-SHA1\'}, but new types may be
defined in the future.
@type assoc_type: C{str}'

def __init__(self, handle, secret, issued, lifetime, assoc_type):

    if (assoc_type not in all_association_types):
        fmt = '%r    is    not    a    supported    association    type'
        raise ValueError((fmt % (assoc_type,)))
    self.handle = handle
    self.secret = secret
    self.issued = issued
    self.lifetime = lifetime
    self.assoc_type = assoc_type
