Output of the transmit.py format

hii,
I am new to gnu radio, and i successfully done the Fm demodulation.
then
i tried to transmit the data. for this i chose the example in
gnuradio-examples/python/digital . transmit.py.
When I executed that example, I got the out put as" >>> gr_fir_fff:
using
SSE
…and
so
on. " I am sure that the data is getting transmitted but my question
is
why the data is in the form of ‘dots’. Is there any way we can see what
the
data packets contains , i mean the signal energy level etc or the
modulated
data sequence like 1, -1 etc
Thank you