ch01

ch01/README.md

@@ -0,0 +1,6 @@
+Chapter 1 data files
+====================
+
+The files in this folder are not supposed to work if run.
+They serve as source for the book chapters, and to provide a
+quick copy/paste tool for whoever would need their content.

ch01/bike.py

@@ -0,0 +1,22 @@
+# let's define the class Bike
+class Bike:
+
+    def __init__(self, colour, frame_material):
+        self.colour = colour
+        self.frame_material = frame_material
+
+    def brake(self):
+        print("Braking!")
+
+# let's create a couple of instances
+red_bike = Bike('Red', 'Carbon fiber')
+blue_bike = Bike('Blue', 'Steel')
+
+# let's inspect the objects we have, instances of the Bike class.
+print(red_bike.colour)  # prints: Red
+print(red_bike.frame_material)  # prints: Carbon fiber
+print(blue_bike.colour)  # prints: Blue
+print(blue_bike.frame_material)  # prints: Steel
+
+# let's brake!
+red_bike.brake()  # prints: Braking!

ch01/factorial.py

@@ -0,0 +1,3 @@
+>>> from math import factorial
+>>> factorial(5)
+120

ch01/names.py

@@ -0,0 +1,19 @@
+>>> n = 3  # integer number
+>>> address = "221b Baker Street, NW1 6XE, London"  # Sherlock Holmes' address
+>>> employee = {
+...     'age': 45,
+...     'role': 'CTO',
+...     'SSN': 'AB1234567',
+... }
+>>> # let's print them
+>>> n
+3
+>>> address
+'221b Baker Street, NW1 6XE, London'
+>>> employee
+{'age': 45, 'role': 'CTO', 'SSN': 'AB1234567'}
+>>> other_name
+Traceback (most recent call last):
+  File "<stdin>", line 1, in <module>
+NameError: name 'other_name' is not defined
+>>>

ch01/scopes1.py

@@ -0,0 +1,14 @@
+# Local versus Global
+
+# we define a function, called local
+def local():
+    m = 7
+    print(m)
+
+# we define m within the global scope
+m = 5
+
+# we call, or `execute` the function local
+local()
+
+print(m)

ch01/scopes2.py

@@ -0,0 +1,12 @@
+# Local versus Global
+
+def local():
+    # m doesn't belong to the scope defined by the local function
+    # so Python will keep looking into the next enclosing scope.
+    # m is finally found in the global scope
+    print(m, 'printing from the local scope')
+
+m = 5
+print(m, 'printing from the global scope')
+
+local()

ch01/scopes3.py

@@ -0,0 +1,20 @@
+# Local, Enclosing and Global
+
+
+def enclosing_func():
+    m = 13
+
+    def local():
+        # m doesn't belong to the scope defined by the local
+        # function so Python will keep looking into the next
+        # enclosing scope. This time m is found in the enclosing
+        # scope
+        print(m, 'printing from the local scope')
+
+    # calling the function local
+    local()
+
+m = 5
+print(m, 'printing from the global scope')
+
+enclosing_func()

ch01/virtualenv.creation.txt

@@ -0,0 +1,65 @@
+Ubuntu 20.04
+
+https://www.liquidweb.com/kb/how-to-install-and-update-python-to-3-9-in-ubuntu
+
+# optional installation steps
+fab@fvm:~$ sudo apt-get update
+fab@fvm:~$ sudo apt-get install software-properties-common
+fab@fvm:~$ sudo add-apt-repository ppa:deadsnakes/ppa
+fab@fvm:~$ sudo apt-get update
+fab@fvm:~$ sudo apt-get install python3.9 python3.9-venv python3.9-dev
+
+fab@fvm:~/srv$ mkdir my-project  # step 1
+fab@fvm:~/srv$ cd my-project
+
+fab@fvm:~/srv/my-project$ which python3.9  # check system python
+/usr/bin/python3.9  # <-- system python3.9
+
+fab@fvm:~/srv/my-project$ python3.9 -m venv lpp3ed  # step 2
+fab@fvm:~/srv/my-project$ source ./lpp3ed/bin/activate  # step 3
+
+# check python again: now using the virtual environment's one
+(lpp3ed) fab@fvm:~/srv/my-project$ which python
+/home/fab/srv/my-project/lpp3ed/bin/python
+
+(lpp3ed) fab@fvm:~/srv/my-project$ python  # step 4
+Python 3.9.2 (default, Feb 20 2021, 20:56:08)
+[GCC 9.3.0] on linux
+Type "help", "copyright", "credits" or "license" for more information.
+>>> exit()
+
+(lpp3ed) fab@fvm:~/srv/my-project$ deactivate  # step 5
+fab@fvm:~/srv/my-project$
+
+
+----------------------------------------------------------------------------------------
+
+Windows 10
+Simply install from python website, then from terminal:
+
+C:\Users\Fab\srv>mkdir my-project  # step 1
+
+C:\Users\Fab\srv>cd my-project
+
+C:\Users\Fab\srv\my-project>where python  # check system python
+C:\Users\Fab\AppData\Local\Programs\Python\Python39\python.exe
+C:\Users\Fab\AppData\Local\Microsoft\WindowsApps\python.exe
+
+C:\Users\Fab\srv\my-project>python -m venv lpp3ed  # step 2
+
+C:\Users\Fab\srv\my-project>lpp3ed\Scripts\activate  # step 3
+
+# check python again, now virtual env python is listed first
+(lpp3ed) C:\Users\Fab\srv\my-project>where python
+C:\Users\Fab\srv\my-project\lpp3ed\Scripts\python.exe
+C:\Users\Fab\AppData\Local\Programs\Python\Python39\python.exe
+C:\Users\Fab\AppData\Local\Microsoft\WindowsApps\python.exe
+
+(lpp3ed) C:\Users\Fab\srv\my-project>python  # step 4
+Python 3.9.2 (tags/v3.9.2:1a79785, Feb 19 2021, 13:44:55)
+⇢ [MSC v.1928 64 bit (AMD64)] on win32
+Type "help", "copyright", "credits" or "license" for more information.
+>>> exit()
+
+(lpp3ed) C:\Users\Fab\srv\my-project>deactivate  # step 5
+C:\Users\Fab\srv\my-project>