'Upgrades all packages of the system.
Optionally, upgrade individual packages.
:param name: Optional parameter wildcard spec to upgrade
:type name: str'

def upgrade(self, name=None):

    if (not name):
        u_cmd = (self.base_command + '    update    -l')
    else:
        u_cmd = ((((self.base_command + '    ') + 'update') + '    ') + name)
    try:
        utils.system(u_cmd)
        return True
    except error.CmdError:
        return False
