@classmethod<EOL><INDENT>def validate_config(cls, config):<DEDENT>
if "<STR_LIT>" not in config:<EOL><INDENT>raise ValueError("<STR_LIT>")<EOL><DEDENT>installed_balancers = Balancer.get_installed_classes().keys()<EOL>if not any([balancer in config for balancer in installed_balancers]):<EOL><INDENT>raise ValueError("<STR_LIT>")<EOL><DEDENT>
Validates a config dictionary parsed from a cluster config file.

Checks that a discovery method is defined and that at least one of
the balancers in the config are installed and available.