DOC: Adding example to head and tail method (pandas-dev#16416)

Author: Cheukting

pandas/core/generic.py

@@ -3563,6 +3563,36 @@ def head(self, n=5):
         -------
         obj_head : type of caller
             The first n rows of the caller object.
+            
+        Examples
+        --------
+        >>> df = pd.DataFrame({'animal':['falcon', 'parrot', 'lion',
+        ...                   'monkey', 'shark', 'bee', 'bear']})
+        >>> df
+           animal
+        0  falcon
+        1  parrot
+        2    lion
+        3  monkey
+        4   shark
+        5     bee
+        6    bear
+          
+        Viewing the last 5 lines (the default)        
+        >>> df.head()        
+           animal
+        0  falcon
+        1  parrot
+        2    lion
+        3  monkey
+        4   shark
+          
+        Viewing the last n lines (three in this case)        
+        >>> df.head(3)        
+           animal
+        0  falcon
+        1  parrot
+        2    lion
         """
 
         return self.iloc[:n]
@@ -3580,6 +3610,37 @@ def tail(self, n=5):
         -------
         obj_tail : type of caller
             The last n rows of the caller object.
+            
+        Examples
+        --------
+        >>> df = pd.DataFrame({'animal':['falcon', 'parrot', 'lion',
+        ...                   'monkey', 'shark', 'bee', 'bear']})
+        >>> df
+           animal
+        0  falcon
+        1  parrot
+        2    lion
+        3  monkey
+        4   shark
+        5     bee
+        6    bear
+          
+        Viewing the last 5 lines (the default)        
+        >>> df.tail()        
+           animal
+        2    lion
+        3  monkey
+        4   shark
+        5     bee
+        6    bear
+          
+        Viewing the last n lines (three in this case)        
+        >>> df.tail(3)        
+          animal
+        4  shark
+        5    bee
+        6   bear
+            
         """
 
         if n == 0: