notes.txt

~ pip
    pip install camelcase
    pip uninstall camelcase
    upgrade: c:\users\user-pc\appdata\local\programs\python\python39\python.exe -m pip install --upgrade pip
    pip list (list packages)

~ install mysql connector
python -m pip install mysql-connector-python

~ frameworks
    larger projects
        https://www.djangoproject.com/
        https://www.turbogears.org/index.html
        https://www.zope.org/

    smaller projects
        https://flask.palletsprojects.com/en/2.0.x/
        https://github.com/MasoniteFramework/masonite (Laravel-like)
        https://geekflare.com/best-python-frameworks/

~ style guide
    https://www.python.org/dev/peps/pep-0008/#introduction
    https://www.flake8rules.com/

~ cmd
    python
    exit()

~ version
    python --version

~ rules
    indentation needs to be the same in a code block
        https://www.flake8rules.com/rules/E111.html

    file needs to end with an empty line
        https://www.flake8rules.com/rules/W292.html

    comments need a space before the text
        # This is a comment.
        https://www.flake8rules.com/rules/E265.html
        at least two spaces for an inline comment

     two lines before and after a class or function name
        https://www.flake8rules.com/rules/E302.html

~ casting
    x = str(3)    # x will be '3'
    y = int(3)    # y will be 3
    z = float(3)  # z will be 3.0

~ get type
type(x)

~ legal variable names
    myvar = "John"
    my_var = "John"
    _my_var = "John"
    myVar = "John"
    MYVAR = "John"
    myvar2 = "John"

~ one value, multiple variables
    x = y = z = "Orange"
    print(x)
    print(y)
    print(z)

~ multiple variables, multiple values
    x, y, z = "Orange", "Banana", "Cherry"
    print(x)
    print(y)
    print(z)

~ unpacking variables
    fruits = ["apple", "banana", "cherry"]
    x, y, z = fruits
    print(x)
    print(y)
    print(z)

~ data types
    Text Type:	str
    Numeric Types:	int, float, complex
    Sequence Types:	list, tuple, range
    Mapping Type:	dict
    Set Types:	set, frozenset
    Boolean Type:	bool
    Binary Types:	bytes, bytearray, memoryview

    x = "Hello World"	str
    x = 20	int
    x = 20.5	float
    x = 1j	complex
    x = ["apple", "banana", "cherry"]	list
    x = ("apple", "banana", "cherry")	tuple
    x = range(6)	range
    x = {"name" : "John", "age" : 36}	dict
    x = {"apple", "banana", "cherry"}	set
    x = frozenset({"apple", "banana", "cherry"})	frozenset
    x = True	bool
    x = b"Hello"	bytes
    x = bytearray(5)	bytearray
    x = memoryview(bytes(5))	memoryview

~ random number
    import random

    print(random.randrange(1, 10))

~ multiline strings
    a = """Lorem ipsum dolor sit amet,
    consectetur adipiscing elit,
    sed do eiusmod tempor incididunt
    ut labore et dolore magna aliqua."""
    print(a)

    a = '''Lorem ipsum dolor sit amet,
    consectetur adipiscing elit,
    sed do eiusmod tempor incididunt
    ut labore et dolore magna aliqua.'''
    print(a)

~ string stuff
    a = "Hello, World!"
    print(a[1])

    for x in "banana":
        print(x)

    a = "Hello, World!"
    print(len(a))

    txt = "The best things in life are free!"
    if "free" in txt:
      print("Yes, 'free' is present.")

    formatting
        https://www.w3schools.com/python/ref_string_format.asp

~ arrays / collections
    List is a collection which is ordered and changeable. Allows duplicate members. [] square brackets
    Tuple is a collection which is ordered and unchangeable. Allows duplicate members. () round brackets
    Set is a collection which is unordered and unindexed. No duplicate members. {} curly brackets
    Dictionary is a collection which is ordered* and changeable. No duplicate members. {} curly brackets (php associative array, json like)