class and name space

 https://docs.python.org/3/tutorial/classes.html

Functions

Defining Functions

We can create a function that writes the Fibonacci series to an arbitrary boundary:

def fib(n):    # write Fibonacci series less than n
    """Print a Fibonacci series less than n."""
    a, b = 0, 1
    while a < n:
        print(a, end=' ')
        a, b = b, a+b
    print()

# Now call the function we just defined:
fib(2000)
0 1 1 2 3 5 8 13 21 34 55 89 144 233 377 610 987 1597 

The keyword def introduces a function definition. It must be followed by the function name and the parenthesized list of formal parameters. The statements that form the body of the function start at the next line, and must be indented. 

A function definition associates the function name with the function object in the current symbol table. The interpreter recognizes the object pointed to by that name as a user-defined function. Other names can also point to that same function object and can also be used to access the function:

fib
<function fib at 10042ed0>
f = fib
f(100)
0 1 1 2 3 5 8 13 21 34 55 89

Return value.

It is simple to write a function that returns a list of the numbers of the Fibonacci series, instead of printing it:

def fib2(n):  # return Fibonacci series up to n
    """Return a list containing the Fibonacci series up to n."""
    result = []
    a, b = 0, 1
    while a < n:
        result.append(a)    # see below
        a, b = b, a+b
    return result

f100 = fib2(100)    # call it
f100                # write the result
[0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89]

This example, as usual, demonstrates some new Python features:

• The return statement returns with a value from a function. return without an expression argument returns None. Falling off the end of a function also returns None.

• The statement result.append(a) calls a method of the list object result. A method is a function that ‘belongs’ to an object and is named obj.methodname, where obj is some object (this may be an expression), and methodname is the name of a method that is defined by the object’s type. Different types define different methods. Methods of different types may have the same name without causing ambiguity. (It is possible to define your own object types and methods, using classes, see Classes) The method append() shown in the example is defined for list objects; it adds a new element at the end of the list. In this example it is equivalent to result = result + [a], but more efficient.

4.9.1. Default Argument Values

The most useful form is to specify a default value for one or more arguments. This creates a function that can be called with fewer arguments than it is defined to allow. For example:

def ask_ok(prompt, retries=4, reminder='Please try again!'):
    while True:
        reply = input(prompt)
        if reply in {'y', 'ye', 'yes'}:
            return True
        if reply in {'n', 'no', 'nop', 'nope'}:
            return False
        retries = retries - 1
        if retries < 0:
            raise ValueError('invalid user response')
        print(reminder)

This function can be called in several ways:

• giving only the mandatory argument: ask_ok('Do you really want to quit?')

• giving one of the optional arguments: ask_ok('OK to overwrite the file?', 2)

• or even giving all arguments: ask_ok('OK to overwrite the file?', 2, 'Come on, only yes or no!')

This example also introduces the in keyword. This tests whether or not a sequence contains a certain value.

The default values are evaluated at the point of function definition in the defining scope, so that

i = 5

def f(arg=i):
    print(arg)

i = 6
f()

will print 5.

Important warning: The default value is evaluated only once. This makes a difference when the default is a mutable object such as a list, dictionary, or instances of most classes. For example, the following function accumulates the arguments passed to it on subsequent calls:

def f(a, L=[]):
    L.append(a)
    return L

print(f(1))
print(f(2))
print(f(3))

This will print

[1]
[1, 2]
[1, 2, 3]

If you don’t want the default to be shared between subsequent calls, you can write the function like this instead:

def f(a, L=None):
    if L is None:
        L = []
    L.append(a)
    return L

Positional, Tuple, and Dictionary Arguments
Output

def fn(pos, *args, **kwargs):
    print("Positional argument:", pos)
    print("Tuple argument:", args)
    print("Dictionary argument:", kwargs)

fn('Placencio', 100, 300, 200, name='Ambiorix', lastname='Rodriguez')
Positional argument: Placencio
Tuple argument: (100, 300, 200)
Dictionary argument: {'name': 'Ambiorix', 'lastname': 'Rodriguez'}

fn('Placencio', 100, 300, 200, name='Ambiorix', lastname='Rodriguez')

https://docs.python.org/3/tutorial/controlflow.html#defining-functions

Topics

https://docs.python.org/3/reference/lexical_analysis.html

function parameters

 # 1️⃣ *args — Extra positional parameters

def print_numbers(*args):

    print("Positional numbers:", args)

print_numbers(1, 2, 3, 4)

# Output:

# Positional numbers: (1, 2, 3, 4)

print()

# 2️⃣ **kwargs — Extra keyword parameters

def print_info(**kwargs):

    print("Keyword info:", kwargs)

print_info(name="Alice", age=17, country="FR")

# Output:

# Keyword info: {'name': 'Alice', 'age': 17, 'country': 'FR'}

print()

# 3️⃣ * — Force keyword-only arguments

def connect(host, port, *, timeout=5, ssl=False):

    print(host, port, timeout, ssl)

connect("localhost", 5432, timeout=10, ssl=True)

# Output:

# localhost 5432 10 True

print()

# 4️⃣ ** in a call — Unpack dict into keywords

def greet(name, age):

    print(f"Hello {name}, you are {age} years old!")

data = {"name": "Bob", "age": 20}

greet(**data)

# Output:

# Hello Bob, you are 20 years old!

print()

# 5️⃣ Combined example with all of them

def full_example(a, b, *args, c=10, **kwargs):

    print("a, b:", a, b)

    print("args:", args)

    print("c:", c)

    print("kwargs:", kwargs)

full_example(1, 2, 3, 4, 5, c=99, x=100, y=200)

# Output:

# a, b: 1 2

# args: (3, 4, 5)

# c: 99

# kwargs: {'x': 100, 'y': 200}

iterating

 >>> i=0

>>> while i<len(a.keys()):

...    print(a[list(a.keys())[i]])

...    i=i+1

... 

Ambiorix

43

195

---------

for key in a:

    print(a[key])

-------------

for value in a.values():

    print(value)

Pyhon Exception

 try:

    result = 10 / a

except Exception as e:

    print(f"An unexpected error occurred: {e}")

else:

    print("Codigo funciona")

finally:

    print("Siempre corre")

python generators

# Online Python compiler (interpreter) to run Python online.

# Write Python 3 code in this online editor and run it.

def  test(i):

    n=0

    while n<i:

        if n==3:

            yield 'We reached the limit'

        else:

            

          yield n

        n=n+1

m=test(24)

print(next(m))

print(next(m))

print(next(m))

print(next(m))

///////

0

1

2

We reached the limit

while and if

 i=0

m=True

while m:

    print(i)

    i+=1

    if i==10:

        m=False

0

1

2

3

4

5

6

7

8

9

find missing number from a list range

 l1=[1,2,5,6]

l2=[7, 1, 3, 5, 6]

def find_missing_number(l1):

    max_n=max(l1)+1

    min_n=min(l1) 

    c=[a for a in range(min_n,max_n) ]

    missing_n=[a for a in c if a not in l1]

    return missing_n

print(find_missing_number(l1))

print(find_missing_number(l2))

[3, 4]

[2, 4]

using cases with dict

def mycase(v):

    d={"A":13,"B":14,"C":22}

    if v in d.keys():

        return d[v]

    else:

        return 0

print(mycase("C"))

https://cloud.google.com/video-intelligence/docs/streaming/live-streaming

 https://cloud.google.com/video-intelligence/docs/streaming/live-streaming

Python Range

 >>> 

>>> [a for a in range(2,11,2) ]

[2, 4, 6, 8, 10]

>>> [a for a in range(2,11,2) if a>4]

[6, 8, 10]

>>> [a**2 for a in range(2,11,2) if a>4]

[36, 64, 100]

>>> 

filtering a list with other list

>>> l=[a for a in l if a not in ['Casa',0]]

>>> l

['Television', 10, 'Pistola']

 

>>> l=[a for a in l if a not in ['Casa',0]]

>>> l

['Television', 10, 'Pistola']

Switch Match

 >>> def http(e):

...    match e:

...       case 400:

...          print('Error 400')

...       case 401:

...          print('Auth request')

...       case _:

...          print('Unknow error')

... 

>>> http(12)

Unknow error

>>> http(500)

Unknow error

>>> http(400)

Error 400

OpenAI API Realtime TTS and Speech to Text

 https://platform.openai.com/docs/guides/realtime-websocket?websocket-examples=python

getting key from a dict based on a value

 >>> users

{'Hans': 'active', 'Éléonore': 'inactive', '景太郎': 'active'}

>>> [a for a in users.keys() if users.get(a)=='active']

['Hans', '景太郎']

getting only str o int values from a dict

 >>> r

{'Name': 'Ambiorix', 'age': 34}

>>> {r[a]:a for a in r if type(r[a])==int}

{34: 'age'}

>>> {r[a]:a for a in r if type(r[a])==str}

{'Ambiorix': 'Name'}

dict practice

 >>> 

>>> 

>>> answer

'Ambiorix Rodriguez Placencio'

>>> chr(max({a:ord(a) for a in answer}.values()))

'z'

>>> chr(max({a:ord(a) for a in answer}.values()))

accessing to dict values

 Code that modifies a collection while iterating over that same collection can be tricky to get right. Instead, it is usually more straight-forward to loop over a copy of the collection or to create a new collection:

# Create a sample collection
users = {'Hans': 'active', 'Éléonore': 'inactive', '景太郎': 'active'}

# Strategy:  Iterate over a copy
for user, status in users.copy().items():
    if status == 'inactive':
        del users[user]

# Strategy:  Create a new collection
active_users = {}
for user, status in users.items():
    if status == 'active':
        active_users[user] = status

reading a file

import os

import sys

def search_key_value(file_path, search_key):

    # Open and read the file safely using a context manager

    with open(file_path, 'r') as file:

        lines = file.readlines()

    # Create a dictionary from the parsed list

    parsed_dict = {line.strip().split(',')[0]: line.strip().split(',')[1] for line in lines}

    # Return the value associated with the search key if it exists

    return parsed_dict.get(search_key)

# Example usage:

file_path = '/var/www/html/fwlist.conf'

sound_folder = '/var/lib/asterisk/sounds/en/custom/'

search_key = sys.argv[1]

file = search_key_value(file_path, search_key)

if file:

    print(f"The value for key '{search_key}' is: {file}")

    # Check if the corresponding file exists

    file_path = sound_folder + file

    print(1 if os.path.isfile(file_path) else 0)

else:

    print(f"Key '{search_key}' not found.")

    print(0)

#############

849,hello

829,goodbye

809,version_2