Attribute error

hey,

I have been working with Eigen value detection in GNU Radio…I am new to
this and i get the following error whenever i execute the flowgraph in
GRC.

File “/home/abhishek/top_block.py”, line 53, in init
self.howto_detect_ff_0 = howto.detect_ff(100, 16, 1500)
AttributeError: ‘module’ object has no attribute ‘detect_ff’

Done

Any help will be appreciated,
Thanks in advance,
Abhishek