Merge pull request joelgrus#15 from pandeesh/patch-1

Update introduction.py

Author: joelgrus

code/introduction.py

@@ -130,6 +130,8 @@ def most_common_interests_with(user_id):
                         (69000, 6.5), (76000, 7.5),
                         (60000, 2.5), (83000, 10),
                         (48000, 1.9), (63000, 4.2)]
+                        
+from matplotlib import pyplot as plt  # not loaded by default                      
 
 def make_chart_salaries_by_tenure(plt):
     tenures = [tenure for salary, tenure in salaries_and_tenures]
@@ -248,4 +250,4 @@ def predict_paid_or_unpaid(years_experience):
 
     for word, count in words_and_counts.most_common():
         if count > 1:
-            print word, count
+            print word, count