But there is CDL3BLACKCROWS in abstract
:
>>> from talib import abstract
>>> abstract.Function('CDL3BLACKCROWS')
{'name': 'CDL3BLACKCROWS', 'group': 'Pattern Recognition', 'display_name': 'Three Black Crows', 'function_flags': ['Output is a candlestick'], 'input_names': OrderedDict([('prices', ['open', 'high', 'low', 'close'])]), 'parameters': OrderedDict(), 'output_flags': OrderedDict([('integer', ['Line'])]), 'output_names': ['integer']}
And all issues you may report to python's wrapper for TA-Lib author here: https://github.com/mrjbq7/ta-lib/issues