Error when I try to use Embedded Python Block and to return lists of bits from it

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Mar 2, 2020

As you can see, this "Sequences_vectors" python embedded block that I created, has a list of bit sequences and it uses a for cycle to select each sequence and then return them to the next block (Repeat block) to go on in the flowgraph.
I did this to simulate a "Vector Source" block(that takes a _single_ list of bits), but that takes more than a single sequence of bits (in my case, as you can see in the code, there are three sequences).

I'd like to transmit each of these three sequences of bits. How can I do?

If I start the graph, it reports this errors:

Generating: '/Users/user/'

Executing: /opt/local/Library/Frameworks/Python.framework/Versions/2.7/Resources/ -u /Users/user/

handler caught exception: in method 'block_gw_message_type_work_args_return_value_set', argument 2 of type 'int'

Traceback (most recent call last):

  File "/opt/local/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/gnuradio/gr/", line 55, in eval

    try: self._callback()

  File "/opt/local/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/gnuradio/gr/", line 225, in __gr_block_handle

    ) for i in range(noutputs)],

TypeError: in method 'block_gw_message_type_work_args_return_value_set', argument 2 of type 'int'

thread[thread-per-block[1]: <block Sequences_vectors (2)>]: SWIG director method error. Error detected when calling 'feval_ll.eval'

But even if it started without errors, I guess that the python embedded block wouldn't behave as expected. In fact I think it would return one list and stops, since the "return" only works one time and not more than one (so the other two sequences can't be "returned"). So I think my code wouldn't work.
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