'Find a server group in a datacenter by calling the CLC API
:param module: the AnsibleModule instance
:param datacenter: clc-sdk.Datacenter instance to search for the group
:param lookup_group: string name of the group to search for
:return: clc-sdk.Group instance'

@staticmethod
def _find_group(module, datacenter, lookup_group=None):

    if (not lookup_group):
        lookup_group = module.params.get('group')
    try:
        return datacenter.Groups().Get(lookup_group)
    except CLCException:
        pass
    result = ClcServer._find_group_recursive(module, datacenter.Groups(), lookup_group)
    if (result is None):
        module.fail_json(msg=str(((('Unable    to    find    group:    ' + lookup_group) + '    in    location:    ') + datacenter.id)))
    return result
