Chapter 6 Exercise Set 0: Chapter Review¶

Dictionary Operations¶

Give the Python interpreter’s response to each of the following from a continuous interpreter session:

>>> d = {'apples': 15, 'bananas': 35, 'grapes': 12}
>>> d['bananas']

```
>>> d['oranges'] = 20
>>> len(d)
```
```
>>> 'grapes' in d
```
```
>>> 'kiwis' in d
```
```
>>> d.get('apples', 0)
```
```
>>> d.get('pears', 0)
```

>>> d2 = {(3, 2): 15, (1, 3): 35, (7, 4): 12, (6, 1): 42, (5, 5): 19}
>>> d2[(7, 4)]

```
>>> del d2[(1, 3)]
>>> len(d2)
```
```
>>> d2.get((6, 1), 0)
```
```
>>> d2.get((4, 10), 0)
```

Be sure you understand why you get each result.

Fruit Inventory¶

Apply what you have learned in the previous exercises to fill in the body of the function below:

def add_fruit(inventory, fruit, quantity=0):
    """
    Adds quantity of fruit to inventory.

       >>> new_inventory = {}
       >>> add_fruit(new_inventory, 'strawberries', 10)
       >>> 'strawberries' in new_inventory
       True
       >>> new_inventory['strawberries']
       10
       >>> add_fruit(new_inventory, 'strawberries', 25)
       >>> new_inventory['strawberries']
       35
     """

Your solution should pass the doctests.

Hello File!¶

Use Python to create a file named hello_file.txt with text that reads:

Hello, this is [name] here, writing in a text file with Python!

with your name substituted for [name].

List From a File¶

Write a Python program that opens a file named list.txt containing a list of items, one per line, reads in the data, and turns them into a Python list. For example, if list.txt contains:

this
that
stuff
such

Your program should create the python list:

['this', 'that', 'stuff', 'such']

Numbers From a File¶

Write a Python program that opens a file named numbers.txt containing a list of integers, one per line, reads in the data, and turns them into a Python list. For example, if numbers.txt contains:

Your program should create the python list:

[13, 97, 42, 17, 11]