Better explain quickstart example

README.md

@@ -76,9 +76,10 @@ y = 2*np.cos(X[:, 3]) + X[:, 0]**2 - 2
 
 # Learn equations
 equations = pysr(X, y, niterations=5,
-        binary_operators=["plus", "mult"],
-        unary_operators=["cos", "exp", "sin", "inv(x) = 1/x"])
-        # Define your own operator with Julia syntax!
+    binary_operators=["plus", "mult"],
+    unary_operators=[
+      "cos", "exp", "sin", #Pre-defined library of operators (see https://pysr.readthedocs.io/en/latest/docs/operators/)
+      "inv(x) = 1/x"]) # Define your own operator! (Julia syntax)
 
 ...# (you can use ctl-c to exit early)