def get_parm_val(parm=None, key=None):
    """
    Return the value of a key

    >>> get_parm_val(parm={'test':'val'},key='test')
    'val'
    >>> get_parm_val(parm={'test':'val'},key='foo')
    >>>
    """
    if parm and key in parm.keys():
        return parm[key]
