[Discuss-gnuradio] Duplicate Packet Header Generator block

Hi,

I would duplicate the Packet Header Generator block, for make some changes in a second time. For this reason I create a tagged_stream block and copy exactly all from the native block, with the new name.
When I open GRC, there is this warning:

    Warning: restarting the docstring loader (crashed while loading 'ofdm_allocator_allocator_alix')
    Warning: restarting the docstring loader (crashed while loading 'ofdm_allocator_allocator_subcarrier')
    Warning: restarting the docstring loader (crashed while loading 'ofdm_allocator_allocator_subcarrier_alix')
    Warning: restarting the docstring loader (crashed while loading 'ofdm_allocator_ofdm_tx')
    Warning: restarting the docstring loader (crashed while loading 'ofdm_allocator_packet_header_default_alix')
    Warning: docstring loader crashed too often

and if I try to import my module in python, it say segmentation fault.
I understood that it depends on packet_header_default object, so I duplicated it in my project with a new name.
No errors, but when I replace native block with my own block and click run, this is the error that appears:

Using Volk machine: avx2_64_mmx_orc
Traceback (most recent call last):
  File "/home/alice/project_GNURADIO/tx_ofdm.py", line 280, in <module>
    main()
  File "/home/alice/project_GNURADIO/tx_ofdm.py", line 274, in main
    tb = top_block_cls()
  File "/home/alice/project_GNURADIO/tx_ofdm.py", line 102, in __init__
    self.ofdm_allocator_packet_header_gen_0 = ofdm_allocator.packet_header_gen(header_formatter.formatter(), length_tag_key)
  File "/usr/local/lib/python2.7/dist-packages/ofdm_allocator/ofdm_allocator_swig.py", line 1553, in make
    return _ofdm_allocator_swig.packet_header_gen_make(*args)
NotImplementedError: Wrong number or type of arguments for overloaded function 'packet_header_gen_make'.
  Possible C/C++ prototypes are:
    gr::ofdm_allocator::packet_header_gen::make(gr::ofdm_allocator::packet_header_default_alix::sptr const &,std::string const &)
    gr::ofdm_allocator::packet_header_gen::make(long,std::string const &)

Any ideas?

Thank you in advance,
Alice