Python 3.8.10 : My colab tutorials and news from colab - part 034.

I add a new colab notebook with a simple source code to list all running VM processes from the colab notebook

You can see more examples on my GitHub colab google repo.

This is the source code:

%%sh
echo "List all running VM processes."
ps -ef
echo "Done"

News : About my work and one of my websites.

I would like to bring to the attention of those who follow my activity on my websites and appreciate the inability to continue with one of the websites: free-tutorials.org. It is currently hosted on a free host, but I cannot import it 100%, which has led me not to complete it with new posts. The continuation of the activities there, considering the limited time, will be carried out on my blogs with the defined theme with which I started: Linux - Fedora, Graphics, Python, Pygame.

In the meantime, because the host is expensive and until now someone has helped me to host it on his server, it is possible to sell the domain: free-tutorials.org - I receive purchase offers at my personal Yahoo email address catafest@yahoo.com.

Minimum starting price 250 euros, because the domain is old from 2018.

Python : Fix error user on install with requirements.txt.

The error show like this :

ERROR: Could not install packages due to an OSError: [WinError 5] Access is denied: 'C:\\Python311\\share'
Consider using the `--user` option or check the permissions.

This can be easy fix with :

pip install -r requirements.txt --user

By using the --user flag, the packages will be installed in the user-specific site-packages directory, ensuring that the packages are installed only for the current user and not affecting the system-wide Python installation.

News : OSINT - Open Source Intelligence python course.

For those who want to learn Python in order to: 

• become a really good developer; 
• to take the exam to get into university; 
• to be interviewed for a job.

This course omits VERY many important things and sometimes even recommends what could have been called bad practice. There are things that don't matter when writing small automations for everyday OSINT tasks, but are extremely important when creating serious team projects.

You cam see the project on this GhitHub account.

News : JupyterLab 4.0 released.

The Jupyter contributor community is proud to announce JupyterLab 4.0, the next major release of our full-featured development environment. The package is now available on PyPI and conda-forge. You can upgrade by running pip install --upgrade jupyterlab or conda install -c conda-forge jupyterlab.

You can read more on the official website.

Python Qt6 : Download for youtube with PyQt6.

Simple example with PyQt6 to create an interface to download a video using a URL from youtube.

This simple example has some limitations, the filtering of the results is done according to the possibilities of the pytube mode and only after video, it does not use multithread and it does not have multiple selection possibilities and options. In conclusion, it offers a simple download functionality.

You can see more on my GitHub account.

import sys
from PyQt6.QtWidgets import QApplication, QMainWindow, QWidget, QVBoxLayout, QHBoxLayout, QLineEdit, QPushButton, QProgressBar, QDialog, QComboBox, QLabel, QMessageBox
from PyQt6.QtGui import QIcon, QPixmap
from pytube import YouTube
from PyQt6.QtCore import Qt
from PyQt6.QtWidgets import QDialogButtonBox


class FormatChecker:
    def __init__(self, url):
        self.url = url

    def check_formats(self):
        try:
            yt = YouTube(self.url)
            formats = []
            streams = yt.streams.filter(only_video=True)
            for stream in streams:
                if stream.url:
                    format_info = {
                        'resolution': stream.resolution,
                        'file_extension': stream.mime_type.split("/")[-1]
                    }
                    formats.append(format_info)
                    print(" format_info ",format_info)
            return formats
        except Exception as e:
            print("Error:", str(e))
            return []


class FormatInfo:
    def __init__(self, resolution, file_formats):
        self.resolution = resolution
        self.file_formats = file_formats


class ResolutionDialog(QDialog):
    def __init__(self, formats, parent=None):
        super().__init__(parent)
        self.setWindowTitle("Select Resolution and File Format")
        self.formats = formats

        layout = QVBoxLayout(self)

        self.resolution_combo = QComboBox(self)
        for format_info in formats:
            resolution = format_info.resolution
            self.resolution_combo.addItem(resolution)
        layout.addWidget(self.resolution_combo)

        self.file_format_combo = QComboBox(self)
        self.update_file_formats(self.resolution_combo.currentText())
        layout.addWidget(self.file_format_combo)

        button_box = QDialogButtonBox(QDialogButtonBox.StandardButton.Ok | QDialogButtonBox.StandardButton.Cancel)
        button_box.accepted.connect(self.accept)
        button_box.rejected.connect(self.reject)
        layout.addWidget(button_box)

        self.resolution_combo.currentIndexChanged.connect(self.on_resolution_changed)

    def update_file_formats(self, resolution):
        self.file_format_combo.clear()
        for format_info in self.formats:
            if format_info.resolution == resolution:
                file_formats = format_info.file_formats
                self.file_format_combo.addItems(file_formats)

    def selected_resolution(self):
        return self.resolution_combo.currentText()

    def selected_file_format(self):
        return self.file_format_combo.currentText()

    def on_resolution_changed(self, index):
        resolution = self.resolution_combo.currentText()
        self.update_file_formats(resolution)


class MainWindow(QMainWindow):
    def __init__(self):
        super().__init__()
        self.setWindowTitle("YouTube Downloader - selected - only_video =True")
        self.setFixedWidth(640)

        central_widget = QWidget(self)
        self.setCentralWidget(central_widget)

        layout = QVBoxLayout(central_widget)

        self.url_edit = QLineEdit()
        layout.addWidget(self.url_edit)

        download_button = QPushButton("Download")
        download_button.clicked.connect(self.show_resolution_dialog)
        layout.addWidget(download_button)

        progress_layout = QHBoxLayout()
        layout.addLayout(progress_layout)

        self.progress_bar = QProgressBar()
        self.progress_bar.setTextVisible(True)
        progress_layout.addWidget(self.progress_bar)

        self.progress_icon_label = QLabel(self)
        pixmap = QPixmap("youtube.png")  # Înlocuiți "path_to_icon.png" cu calea către iconul dorit
        self.progress_icon_label.setPixmap(pixmap)
        progress_layout.addWidget(self.progress_icon_label)

    def show_resolution_dialog(self):
        url = self.url_edit.text()
        if url:
            format_checker = FormatChecker(url)
            formats = format_checker.check_formats()
            format_infos = []
            for format in formats:
                resolution = format['resolution']
                file_extension = format['file_extension']
                format_info = next((info for info in format_infos if info.resolution == resolution), None)
                if format_info:
                    format_info.file_formats.append(file_extension)
                else:
                    format_info = FormatInfo(resolution, [file_extension])
                    format_infos.append(format_info)

            dialog = ResolutionDialog(format_infos, self)
            if dialog.exec() == QDialog.DialogCode.Accepted:
                resolution = dialog.selected_resolution()
                file_format = dialog.selected_file_format()
                self.download_video(url, resolution, file_format)
        else:
            print("Please enter a valid YouTube URL.")

    def download_video(self, url, resolution, file_format):
        try:
            yt = YouTube(url)
            stream = yt.streams.filter(only_video=True, resolution=resolution, mime_type="video/" + file_format).first()
            if stream:
                stream.download()
                print("Download completed!")
                QMessageBox.question(self, "Download Completed", "The video has been downloaded successfully.", QMessageBox.StandardButton.Ok)
            else:
                print("Error: The selected video format is not available for download.")
                QMessageBox.question(self, "Download Error", "The selected video format is not available for download.", QMessageBox.StandardButton.Ok)
        except Exception as e:
            print("Error:", str(e))
            QMessageBox.question(self, "Download Error", "An error occurred during the download.", QMessageBox.StandardButton.Ok)


def main():
    app = QApplication(sys.argv)
    window = MainWindow()
    window.show()
    sys.exit(app.exec())


if __name__ == "__main__":
    main()

Python 3.11.0 : Exo - domain-specific programming language in python.

Exo is a domain-specific programming language that helps low-level performance engineers transform very simple programs that specify what they want to compute into very complex programs that do the same thing as the specification, only much, much faster.

You can find it on GitHub project and on the official webpage.

Let's install it with pip tool:

C:\PythonProjects>mkdir exo-lang_001

C:\PythonProjects>cd exo-lang_001

C:\PythonProjects\exo-lang_001>pip install exo-lang --user
Collecting exo-lang
  Downloading exo_lang-0.0.2-py3-none-any.whl (142 kB)
  ...
Successfully installed PySMT-0.9.5 asdl-0.1.5 asdl-adt-0.1.0 astor-0.8.1 exo-lang-0.0.2 tomli-2.0.1 
yapf-0.33.0 z3-solver-4.12.2.0

Let's test with this default example but using virtual environments

This allow me to install Python packages in an isolated location from the rest of your system instead of installing them system-wide.

C:\PythonProjects\exo-lang_001>pip install virtualenv --user
...
C:\PythonProjects\exo-lang_001>python -m venv venv
C:\PythonProjects\exo-lang_001>venv\Scripts\activate.bat

(venv) C:\PythonProjects\exo-lang_001>python -m pip install -U setuptools wheel
Successfully installed setuptools-67.8.0 wheel-0.40.0

[notice] A new release of pip available: 22.3 -> 23.1.2
[notice] To update, run: python.exe -m pip install --upgrade pip
(venv) C:\PythonProjects\exo-lang_001>python.exe -m pip install --upgrade pip
Requirement already satisfied: pip in c:\pythonprojects\exo-lang_001\venv\lib\site-packages (22.3)
Collecting pip
  Using cached pip-23.1.2-py3-none-any.whl (2.1 MB)
...
Successfully installed pip-23.1.2
(venv) C:\PythonProjects\exo-lang_001>python -m pip install exo-lang
...
Installing collected packages: z3-solver, PySMT, asdl, tomli, numpy, attrs, astor, yapf, asdl-adt, exo-lang
Successfully installed PySMT-0.9.5 asdl-0.1.5 asdl-adt-0.1.0 astor-0.8.1 attrs-23.1.0 exo-lang-0.0.2 numpy-1.24.3
tomli-2.0.1 yapf-0.33.0 z3-solver-4.12.2.0

Let's try a simple example from official webpage:

(venv) C:\PythonProjects\exo-lang_001>notepad example.py
# example.py
from __future__ import annotations
from exo import *

@proc
def example_sgemm(
    M: size,
    N: size,
    K: size,
    C: f32[M, N] @ DRAM,
    A: f32[M, K] @ DRAM,
    B: f32[K, N] @ DRAM,
):
    for i in seq(0, M):
        for j in seq(0, N):
            for k in seq(0, K):
                C[i, j] += A[i, k] * B[k, j]

Use this command and check the out folder:

(venv) C:\PythonProjects\exo-lang_001>cd out
(venv) C:\PythonProjects\exo-lang_001\out>dir 
...
 example.c   example.h

If you want to know more see this video from youtube:

Python 3.11.3 : Using Jupyter Lab on Fedora linux distro.

JupyterLab is the latest web-based interactive development environment for notebooks, code, and data. Its flexible interface allows users to configure and arrange workflows in data science, scientific computing, computational journalism, and machine learning.

Follow these steps:

1. Install the jupyterlab python package using pip. This will allow you to run Jupyter notebooks in the terminal.

   pip install jupyterlab

2. Open a Jupyter Lab session in the terminal using the command:

   jupyter lab

3. Create a new notebook file and save it with the .ipynb extension.
4. In the notebook file, add the source code to work with the Python programming language and save the file notebook.

See the next screenshot how this works:

Python 3.8.10 : My colab tutorials and news from colab - part 033.

Colab comes with new changes:

Starting today paid users can select their preferred NVIDIA GPU. Visit Runtime > Change runtime type and choose between T4, V100, and A100. We'll do our best to assign your choice based on GPU availability.

Today I tested a new python package called News API with colab to search for news.

News API is a simple, easy-to-use REST API that returns JSON search results for current and historic news articles published by over 80,000 worldwide sources.

You can find my sample code in my collaboration area of the GitHub repository.

Extension for inkscape with python.

Today, I created the first Python extension for Inkscape, and although in theory, it seems easy, it is not really so.

You have to study a little and search the web, but I created a tutorial on one of my website.

The idea is to use at least two files with different extensions.

I named one catafest_extension.inx and the other catafest_extension.py.

For the Python file, I used this source code:

#!/usr/bin/env python
# coding=utf-8
#
# Copyright (C) 2023 Catalin George Festila, catafest@yahoo.com
#

"""
Simple test extension for inkscape
"""

import inkex
# add by me 

from lxml import etree
def draw_SVG_square(w,h, x,y, parent):
    style = { 'stroke'        : 'none',
              'stroke-width'  : '1',
              'fill'          : '#0000FF'
            }

    attribs = {
        'style'     : str(inkex.Style(style)),
        'height'    : str(h),
        'width'     : str(w),
        'x'         : str(x),
        'y'         : str(y)
            }
    patrat = etree.SubElement(
        parent, inkex.addNS('rect','svg'), attribs )
    return patrat

class MyExtension(inkex.Effect):
    def __init__(self):
        super().__init__()

    def effect(self):
        self.msg("This is an empty extension created by catafest !")
        parent = self.svg.get_current_layer()
        draw_SVG_square(100,100, 0,0, parent)

if __name__ == '__main__':
    MyExtension().run()

The result is this

Python 3.8.10 : My colab tutorials - part 032.

I haven't written for the python community in a long time, here is another example that I created using a tool from google called colab.

catafest_038.ipynb - simple example with StableDiffusionPipeline and DiffusionPipeline to generate images based a text ...

This and the other examples can be found in my repository named colab_google on my GitHub account.

Python Qt6 : use sqlite - part 002.

In this article tutorial I will show you how to read from the sqlite file the content of the table: files.

In the last article tutorial, I create a interface with PyQt6 that search files by regular expresion and result is add to sqlite file named: file_paths.db.

I used same steps with a default python class and I used QSqlTableModel to show the content received.

The script will create a window with this QSqlTableModel, then reads the file and add the result.

Let's see the source code:

import sys
from PyQt6.QtWidgets import QApplication, QMainWindow, QTableView
from PyQt6.QtSql import QSqlDatabase, QSqlQuery, QSqlTableModel

class MainWindow(QMainWindow):
    def __init__(self):
        super().__init__()

        # Initialize the database
        self.init_db()

        # Set up the GUI
        self.table_view = QTableView(self)
        self.setCentralWidget(self.table_view)

        # Set up the model and connect it to the database
        self.model = QSqlTableModel(self)
        self.model.setTable('files')
        self.model.select()
        self.table_view.setModel(self.model)

    def init_db(self):
        # Connect to the database
        db = QSqlDatabase.addDatabase('QSQLITE')
        db.setDatabaseName('file_paths.db')
        if not db.open():
            print('Could not open database')
            sys.exit(1)

    def create_table(self):
        # Create the 'files' table if it doesn't exist
        query = QSqlQuery()
        query.exec('CREATE TABLE IF NOT EXISTS files (id INTEGER PRIMARY KEY, path TEXT)')

if __name__ == '__main__':
    app = QApplication(sys.argv)
    window = MainWindow()
    window.show()
    sys.exit(app.exec())

I add this source code into a python script named view.py and I run it.

This is the result of the running script:

Python Qt6 : use sqlite - part 001.

This will default update for any python project:

python.exe -m pip install --upgrade pip --user
...
Successfully installed pip-23.1

The sqlite3 is already on my python instalation because I use version 3.11.0, you can see the official webpage.

Install the PyQt6 with the pip tool, I have this python package:

pip install PyQt6 --user
Requirement already satisfied: PyQt6 in c:\python311\lib\site-packages (6.4.1)
...

The next source of code will create a windows with two buttons and one edit area.

The PyQt6 graphics user interface use these elements: QPushButton, QLineEdit and QMessageBox from QWidget.

The python class will create a window with these elements and dor each of these is need to have methods.

First you need to select the folder, then use an regular expresion for search.

I used this : .*\.blend1$ this means *.blend1.

The last step is to use FindFiles button to search all blend files, in this case and add path of each of these to the sqlite database into a table named: files .

If you select the root C: then will take some time to search the files.

Let's see the source code:

import sys
import os
import re
from PyQt6.QtWidgets import *
from PyQt6.QtCore import *
import sqlite3

class FindFiles(QWidget):
    def __init__(self):
        super().__init__()
        self.setWindowTitle("Find Files")
        self.setGeometry(100, 100, 500, 300)

        self.folder_button = QPushButton("Choose Folder")
        self.folder_button.clicked.connect(self.choose_folder)
        self.pattern_edit = QLineEdit()
        self.pattern_edit.setPlaceholderText("Enter regular expression pattern")
        self.pattern_edit.setFixedWidth(250)
        self.find_button = QPushButton("Find Files")
        self.find_button.clicked.connect(self.find_files)

        layout = QVBoxLayout()
        layout.addWidget(self.folder_button)
        layout.addWidget(self.pattern_edit)
        layout.addWidget(self.find_button)
        self.setLayout(layout)

        self.folder_path = ""

        self.conn = sqlite3.connect("file_paths.db")
        self.cursor = self.conn.cursor()
        self.cursor.execute("CREATE TABLE IF NOT EXISTS files (id INTEGER PRIMARY KEY, path TEXT)")

    def choose_folder(self):
        self.folder_path = QFileDialog.getExistingDirectory(self, "Choose Folder")
        if self.folder_path:
            self.folder_button.setText(self.folder_path)

    def find_files(self):
        if not self.folder_path:
            QMessageBox.warning(self, "Warning", "Please choose a folder first!")
            return

        pattern = self.pattern_edit.text()

        if not pattern:
            QMessageBox.warning(self, "Warning", "Please enter a regular expression pattern!")
            return

        file_paths = []
        for root, dirs, files in os.walk(self.folder_path):
            for file in files:
                if re.match(pattern, file):
                    file_path = os.path.join(root, file)
                    file_paths.append(file_path)
                    self.cursor.execute("INSERT INTO files (path) VALUES (?)", (file_path,))
        self.conn.commit()

        QMessageBox.information(self, "Information", f"Found {len(file_paths)} files that match the pattern!")

if __name__ == "__main__":
    app = QApplication(sys.argv)
    find_files = FindFiles()
    find_files.show()
    sys.exit(app.exec())

I put this source code into a file named:main.py and I run it.

python main.py

The result is this: