Preconfigured versioned expression. If this field is specified,
config must also be specified. Available preconfigured expressions
along with their requirements are: SRC_IPS_V1 - must specify the
corresponding src_ip_range field in config.
Values:
UNDEFINED_VERSIONED_EXPR (0):
A value indicating that the enum field is not
set.
SRC_IPS_V1 (70925961):
Matches the source IP address of a request to
the IP ranges supplied in config.
