'place an env in the env var list'

def update_volume_mount(self, volume_mount):

    modified = False
    exist_volume_mounts = self.get_volume_mounts()
    if (not volume_mount):
        return False
    for exist_vol_mount in exist_volume_mounts:
        if (exist_vol_mount['name'] == volume_mount['name']):
            if (('mountPath' in exist_vol_mount) and (str(exist_vol_mount['mountPath']) != str(volume_mount['mountPath']))):
                exist_vol_mount['mountPath'] = volume_mount['mountPath']
                modified = True
            break
    if (not modified):
        self.add_volume_mount(volume_mount)
        modified = True
    return modified
