More comments to help explain call structure

pysr/sr.py

@@ -1323,6 +1323,8 @@ class PySRRegressor(BaseEstimator, RegressorMixin):
 
         self.params_hash = cur_hash
 
+        # Call to Julia backend.
+        # See https://github.com/search?q=%22function+Options%22+repo%3AMilesCranmer%2FSymbolicRegression.jl+path%3A%2Fsrc%2F+filename%3AOptions.jl+language%3AJulia+language%3AJulia&type=Code&ref=advsearch&l=&l=
         options = Main.Options(
             binary_operators=Main.eval(str(tuple(binary_operators)).replace("'", "")),
             unary_operators=Main.eval(str(tuple(unary_operators)).replace("'", "")),
@@ -1394,6 +1396,8 @@ class PySRRegressor(BaseEstimator, RegressorMixin):
 
         cprocs = 0 if multithreading else procs
 
+        # Call to Julia backend.
+        # See https://github.com/search?q=%22function+EquationSearch%22+repo%3AMilesCranmer%2FSymbolicRegression.jl+path%3A%2Fsrc%2F+filename%3ASymbolicRegression.jl+language%3AJulia+language%3AJulia&type=Code&ref=advsearch&l=Julia&l=Julia
         self.raw_julia_state = Main.EquationSearch(
             Main.X,
             Main.y,