def METHOD_NAME(self, seconds: float) -> "ExpiringAuth":
    """Return a (flat) copy of this object with a new expiration time.
    This is a convenience method for creating an :class:`.ExpiringAuth`
    for a relative expiration time ("expires in" instead of "expires at").
        >>> import time, freezegun
        >>> with freezegun.freeze_time("1970-01-01 00:00:40"):
        ...     ExpiringAuth(("user", "pass")).expires_in(2)
        ExpiringAuth(auth=('user', 'pass'), expires_at=42.0)
        >>> with freezegun.freeze_time("1970-01-01 00:00:40"):
        ...     ExpiringAuth(("user", "pass"), time.time() + 2)
        ExpiringAuth(auth=('user', 'pass'), expires_at=42.0)
    :param seconds:
        The number of seconds from now until the authentication information
        expires.
    .. versionadded:: 5.9
    """
    return ExpiringAuth._without_warning(  # type: ignore
        self.auth, time.time() + seconds
    )