Description of problem:

see that packagegroup can only be installed on individual consumers

[root@preethi ~]# pulp-admin packagegroup install --help
Usage: ... install <options>

Options:
  -h, --help            show this help message and exit
  -g PKGGROUPID, --pkggroupid=PKGGROUPID
                        packagegroup to install on a given consumer; to
                        specify multiple package groups use multiple -g
  --consumerid=CONSUMERID
                        consumer id
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It should match the package install option

[root@preethi ~]# pulp-admin package install --help
Usage: ... install <options>

Options:
  -h, --help            show this help message and exit
  -n PNAMES, --name=PNAMES
                        packages to be installed; to specify multiple packages
                        use multiple -n
  --consumerid=CONSUMERID
                        consumer id
  --consumergroupid=CONSUMERGROUPID
                        consumer group id