Table of contents

  1. Add unspecified options to cli command using python-click
  2. Add text to Existing PDF using Python
  3. How to debug python click cli application?
  4. How to implement --version using python click?
  5. Python Click command names
  6. How to add colour to Excel cells using Python

Add unspecified options to cli command using python-click

In the Python click library, you can add unspecified options to a CLI command by using the @pass_context decorator and the Context object to dynamically add options. Here's how you can achieve this:

import click

class DynamicOptionAdder:
    def __init__(self):
        self.options_to_add = []

    def add_option(self, option):

pass_option_adder = click.make_pass_decorator(DynamicOptionAdder, ensure=True)
@click.option('--global-option', help='A global option')
def cli(option_adder, global_option):

def process(option_adder, value):
    for option in option_adder.options_to_add:
        click.echo(f"Added option: {option}")

if __name__ == '__main__':

In this example, we have a DynamicOptionAdder class that holds the options we want to add dynamically. The @pass_option_adder decorator is used to pass an instance of DynamicOptionAdder to the command functions. The add_option method of DynamicOptionAdder is used to add the options that were passed as arguments.

The cli command group defines a global option --global-option, which will be added dynamically to the subcommands. The process subcommand demonstrates how to use the dynamically added options.

Remember that this approach adds options dynamically but doesn't perform any validation or default value handling for those options. You might need to extend this approach to handle more complex cases and ensure that the dynamically added options are handled correctly.

Add text to Existing PDF using Python

To add text to an existing PDF using Python, you can use the PyPDF2 library. Here's a step-by-step guide to adding text to a PDF file:

  1. Install the PyPDF2 library if you haven't already:

    pip install PyPDF2
  2. Create a Python script to add text to the PDF:

    import PyPDF2
    # Open the existing PDF file
    with open('existing_pdf.pdf', 'rb') as pdf_file:
        pdf_reader = PyPDF2.PdfFileReader(pdf_file)
        pdf_writer = PyPDF2.PdfFileWriter()
        # Iterate through each page of the PDF
        for page_num in range(pdf_reader.getNumPages()):
            page = pdf_reader.getPage(page_num)
            # Create a PDF text object
            pdf_text = PyPDF2.pdf.PageObject.createTextObject("Text to add")
            # Set the font and font size
            pdf_text.setFont("Helvetica-Bold", 12)
            # Set the position of the text on the page (x, y coordinates)
            pdf_text.setTextOrigin(100, 100)
            # Add the text to the page
            # Add the modified page to the PDF writer
        # Save the modified PDF to a new file
        with open('modified_pdf.pdf', 'wb') as output_file:

    Replace 'existing_pdf.pdf' with the name of your existing PDF file and adjust the text, font, font size, and position as needed.

  3. Run the script, and it will create a new PDF file with the added text, named 'modified_pdf.pdf'.

This code opens the existing PDF, iterates through its pages, and adds the specified text to each page. You can customize the text, font, font size, and position according to your requirements.

Make sure to have the PyPDF2 library installed and that you have the necessary permissions to read and write files in the directory where the PDF files are located.

How to debug python click cli application?

Debugging a Python Click CLI application involves using various debugging techniques to identify and fix issues within your code. Here are some steps you can take to debug a Click CLI application:

  1. Print Statements: Start with simple print statements at various points in your code to see the flow of execution and the values of variables. This can help you identify where the issue might be occurring.

  2. Using pdb for Interactive Debugging: Python comes with a built-in debugger called pdb. You can insert breakpoints in your code using the import pdb; pdb.set_trace() statement. When your code reaches this point, it will pause execution, allowing you to interactively inspect variables, step through code, and diagnose issues. Use commands like n (next), c (continue), and p variable_name (print variable) in the debugger.

  3. Using IDE Debuggers: Many integrated development environments (IDEs) offer sophisticated debugging tools. If you're using an IDE like PyCharm, Visual Studio Code, or others, you can set breakpoints, step through code, inspect variables, and watch expressions directly from the IDE.

  4. Handling Click Command Line Arguments: When debugging a Click CLI application, you may need to provide command line arguments to simulate different scenarios. You can do this directly in your IDE's debugger configuration or use the Python debugger pdb.

  5. Logging: Incorporating the Python logging module into your application can provide detailed information about the execution flow, function calls, and variable values. You can set different log levels to control the amount of information printed during debugging.

  6. Exception Handling: Properly handling exceptions and using try-except blocks can provide more insights into what's going wrong. Logging the exception traceback using the logging module can help you identify where the problem lies.

  7. Unit Tests: Write unit tests for your Click CLI commands using a testing framework like unittest or pytest. This can help you isolate specific parts of your code and ensure that they work as expected.

  8. Inspect Command Callbacks: Place debugging statements within the callbacks for your Click commands. This allows you to see how the command callbacks are being invoked and the values being passed.

  9. Run Commands Directly: You can also run your Click commands directly in your Python interpreter to observe their behavior and check for any errors. This can help identify issues that might not be apparent when running the full CLI.

  10. Check Click Documentation: If you encounter issues related to Click's command line parsing and handling, refer to the Click documentation for best practices and troubleshooting information.

By using a combination of these techniques, you can effectively debug your Click CLI application and identify and fix issues in your code.

How to implement --version using python click?

Using the click library in Python, you can implement a --version option for your command-line interface (CLI) application to display the version of your program. Here's how you can do it:

  1. Install click if not already installed:

    Make sure you have the click library installed. You can install it using the following command:

    pip install click
  2. Import click and Create a Command Group:

    Create a Python script for your CLI application and import the click library. Then, use to define a command group for your CLI.

    import click
    def cli():
  3. Define a Version String:

    Set a version string for your application using click.version_option(). This will create a --version option that displays the provided version when invoked.

    VERSION = '1.0.0'  # Replace with your actual version
    def cli():
  4. Add Other Commands:

    If your CLI has other commands, add them to the command group as separate functions using the @cli.command() decorator.

    def command1():
        click.echo("Executing command 1")
    def command2():
        click.echo("Executing command 2")
  5. Run the CLI:

    At the end of your script, run the CLI using if __name__ == '__main__':.

    if __name__ == '__main__':
  6. Run the Application:

    Now, when you run your application, you can use the --version option to display the version string:

    python --version

    This will output:


Replace '1.0.0' with the actual version string of your application. This implementation uses the click library's built-in version option, making it easy to handle version display in your CLI application.

Python Click command names

In the Python click library, you can define command names using the @click.command() decorator. The name you provide to this decorator is the name you'll use to invoke the command from the command line. Here's an example of defining and using command names using the click library:

import click

@click.option('--name', default='World', help='Name to greet')
def greet_command(name):
    """Greet the user."""
    click.echo(f"Hello, {name}!")

@click.option('--name', default='World', help='Name to say goodbye to')
def goodbye_command(name):
    """Say goodbye to the user."""
    click.echo(f"Goodbye, {name}!")

if __name__ == '__main__':

In this example, we have defined two commands: greet and goodbye. The @click.command(name='command_name') decorator specifies the command name. You can run these commands from the command line like this:

python greet --name Alice
python goodbye --name Bob

Where is the name of your Python script file.

The click library allows you to define the CLI structure and options for your Python scripts in a clean and structured way, making it easy to create command-line tools.

How to add colour to Excel cells using Python

To add color to Excel cells using Python, you can make use of the openpyxl library, which provides tools to work with Excel files (.xlsx). Below are the steps to add color to Excel cells using openpyxl:

1. Installation:

First, you need to install openpyxl:

pip install openpyxl

2. Coloring Excel Cells:

Here's a simple example that demonstrates how to add color to Excel cells:

import openpyxl
from openpyxl.styles import PatternFill

# Load the workbook (or create a new one)
wb = openpyxl.Workbook()
ws =

# Write some data
ws["A1"] = "Hello"
ws["A2"] = "World"

# Add color to cells
yellow_fill = PatternFill(start_color="FFFF00", end_color="FFFF00", fill_type="solid")
ws["A1"].fill = yellow_fill

red_fill = PatternFill(start_color="FF0000", end_color="FF0000", fill_type="solid")
ws["A2"].fill = red_fill

# Save the workbook"colored_cells.xlsx")

In the above code:

  • We first create a workbook and get the active worksheet.
  • We then define PatternFill objects for the desired colors. The start_color and end_color parameters accept RGB values in hex format. Here, "FFFF00" represents yellow and "FF0000" represents red.
  • We then assign the fill styles to specific cells.
  • Finally, we save the workbook.

You can customize the above code to color multiple cells or entire rows/columns as per your needs. openpyxl provides a rich set of tools to style Excel files, including setting fonts, borders, and more.

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