returns a list which contains metadata about your query along with a
dataframe containing your candlestick data.
Arguments
instrument
the instrument name which you want to query
timeframe
the timeframe which each candle represents. You can choose
from the following options: '1m', '5m', '15m', '30m', '1h', '4h', '6h',
'12h', '1D', '7D', '14D', '1M'. The defailt option is '5m'.