mplfinance default values rise error in plot function

[rain-philosophy]

Hi!
First of all, thank you for such useful library for plotting candles!

I'm trying to process a scenario, when addplot and alines is empty (at the present moment buys and sells lists have only one point in format ['date','price'], but it doesn't matter for question). So my function, that builds a graph is:

def mplfplotcoin(df,title,
                 buys=[],
                 sells=[],
                 rsi=False):
    
    adp = []

    # adding trades
    if buys: 
        buysdf = pd.DataFrame([buys],columns=['Date', 'OpenPrice']) # when buys list consists of one point
        buysdf = df.merge(buysdf,on='Date',how='left')['OpenPrice'] # left join
        addbuys = mpf.make_addplot(buysdf,scatter=True,markersize=300,marker=6,color='forestgreen',alpha=0.75) # buy markers
        adp.append(addbuys)
    if sells:
        sellsdf = pd.DataFrame([sells], columns=['Date', 'ClosePrice']) # when sells list consists of one point
        sellsdf = df.merge(sellsdf,on='Date',how='left')['ClosePrice'] # left join
        addsells = mpf.make_addplot(sellsdf,scatter=True,markersize=300,marker=7,color='firebrick',alpha=0.75) # sell markers
        adp.append(addsells)
    
    # adding line between trades https://github.com/matplotlib/mplfinance/blob/master/examples/using_lines.ipynb
    if len(buys) == len(sells) and buys: # I know it's awful))) I'll change it later
        tradeline = dict(alines=[tuple(buys),tuple(sells)],colors='lightslategray',linestyle='--',linewidths=2,alpha=0.5)
    else: tradeline = None

    # adding rsi
    if rsi:
        addrsi = mpf.make_addplot((df['rsi']),panel=1,type='line',color='orange',width=1,ylabel='rsi',ylim=(-5,105))
        adp.append(addrsi)

    # checking adp list
    if not adp: adp = None

    # drawing
    mpf.plot(df,
             type='candle',
             style='tradingview',
             volume=True,
             show_nontrading=True,
             addplot=adp,
             alines=tradeline,
             figscale=1.3,
             title=title,
             ylabel='USDT')

so, lines else: tradeline = None and if not adp: adp = None are like this, because I found it in your library file plottin.py:

#211 line:
        'addplot'                   : { 'Default'     : None, 
                                        'Description' : 'addplot object or sequence of addplot objects (from `mpf.make_addplot()`)',
                                        'Validator'   : lambda value: isinstance(value,dict) or (isinstance(value,list) and all([isinstance(d,dict) for d in value])) },

# 267 line:
        'alines'                    : { 'Default'     : None, 
                                        'Description' : 'Draw one or more ARBITRARY LINES anywhere on the plot, by'+
                                                        ' specifying a sequence of two or more date/price pairs, or by'+
                                                        ' specifying a sequence of sequences of two or more date/price pairs.'+
                                                        ' May also be a dict with key `alines` (as date/price pairs described above),'+
                                                        ' plus one or more of the following keys:'+
                                                        ' `colors`, `linestyle`, `linewidths`, `alpha`.',

however I get errors for mpf.plot(..., addplot=adp, alines=tradeline, ...):

TypeError: kwarg "addplot" validator returned False for value: "None"
    'Validator'   : lambda value: isinstance(value,dict) or (isinstance(value,list) and all([isinstance(d,dict) for d in value])) },

and the same for alines parameter:

TypeError: kwarg "alines" validator returned False for value: "None"
    'Validator'   : lambda value: _alines_validator(value) },

If I go to plotting.py, I can't understand why error is rised, because there is only one if about addplot is None:

# 739 line
    addplot = config['addplot']
    if addplot is not None and ptype not in VALID_PMOVE_TYPES:
        ...

# and then 816 line is new condition:
    # fill_between is NOT supported for external_axes_mode
    # (caller can easily call ax.fill_between() themselves).
    if config['fill_between'] is not None and not external_axes_mode:
        ...

Ok, I tried to define ptype in my code:

# checking adp list
if not adp: adp = [mpf.make_addplot(None,type='line')]

But again error:

    raise TypeError('Wrong type for data, in make_addplot()')
TypeError: Wrong type for data, in make_addplot()

Please, help me to understand how to draw plot if addplot and alines (and other kwards) are empty?