Add FIR generators

Closes #152 (closed) #153 (closed)

b_asic/sfg_generators.py

@@ -209,7 +209,7 @@ def transposed_direct_form_fir(
         Union[Dict[str, int], Dict[str, Dict[str, int]]]
     ] = None,
 ):
-    """
+    r"""
     Generate a signal flow graph of a transposed direct form FIR filter. The *coefficients* parameter is a
     sequence of impulse response values::