def pretty_print_dict(dtmp):
    """Pretty prints an un-nested dictionary 

    Parameters
    ----------
    dtmp : dict
    
    Returns
    -------
    str
        pretty-printed dictionary
    """
    ltmp = []
    keys = dtmp.keys()
    maxlen = 2 + max([len(K) for K in keys])
    for k, v in sorted(dtmp.items(), key=lambda x: x[0]):
        if type(v) == type(""):
            v = "'%s'" % v
        new_k = "'%s'" % k
        stmp = ("          {0:<%s} : {1}," % maxlen).format(new_k, v)
        ltmp.append(stmp)

    sout = "\n".join(ltmp)
    return "{\n%s\n}\n" % sout