Python is a high-level, all-purpose programming language. It is extremely versatile and can be used to create desktop GUI programs, websites, and web applications. Also, handling routine programming tasks frees you up to concentrate on the essential features of the application. Moreover, with Python, you can keep the code base readable and the application maintainable more easily thanks to Python’s straightforward syntax rules. How to use a Python script is one of the most crucial skills you can develop as a Python developer.
Naturally, this will be the only way to know if your code works as you planned. So, in this post, we will look at how to use a Python script properly and discuss the types of Python script files available and how they are different from one another.
Table of Contents
What type of language is Python?
There are three main types of programming languages: compiled, scripts or scripting, and interpreted. The primary distinction is that scripting languages are always interpreted while programming languages are either completely compiled down to native machine instructions or are partially compiled to an intermediate ‘tokenized’ form of instructions which then require a runtime to convert those tokens into runnable machine-specific instructions. Python is mainly an “interpreted language,” but its features make it a competent “scripting language.”
What is the difference between a Python script which has a .py extension to one with a .pyc file extension?
Python scripts can be compiled from readable ‘.py’ text files which can be opened by any text editor. The Python scripts can also be compiled into ‘.pyc’ binary files which contain the script as intermediate tokenized instructions which are then converted to machine-specific instructions by the Python runtime. The ‘.pyc’ Python script files are more secure than .py text files since regular users can’t easily open the files and read the program but there are tools readily available which can ‘decompile’ the binary Python .pyc files back into text .py files.
Are Python scripts slower than compiled programs written in other computer languages?
Scripting languages are typically slower than fully compiled programming languages such as Delphi, C++, and C. They may less access to a computer’s native capabilities because they are intended to be able to run as many types of computers and operating system as possible and to do this they avoid some machine-specific functions. Python runtimes handle most of the commonly available hardware such as cameras and networking components but can’t always provide an abstraction for less common hardware or operating system features.
Since it functions as both a compiler and an interpreter, Python acts as both a scripting language and a programming language. For example, a standard Python interpreter can translate Python code into bytecodes like Java and C – the .pyc files we mentioned earlier.
For easy understanding, consider an example Python file, example.py, with the following basic code:
print('This is an example!')
We will use this file for all the tutorials in this article.
Can you run Python scripts interactively?
From an interactive session, Python scripts and modules can be executed. You have several options with this choice.
What occurs when you import a module is that you load its contents for access and use at a later time. The intriguing aspect of this procedure is that import executes the code as its last action.
You probably won’t notice that the code was executed if the module only contains definitions for classes, functions, variables, and constants. Still, you will see the code being executed if it also includes calls to other functions, methods, or statements that produce obvious results.
You should be aware that this option only functions once per session. Even if you change the module’s content after the initial import, subsequent import executions have no further effect. This is because import operations are costly and only occur once.
However, there is a single solution to this.
You can find importlib, a module that offers import_module(), in the Python Standard Library.
You can execute any module or script by simulating an import operation with import_module(). Take a look at this example:
It is impossible to continue running a module using import after the initial import. Therefore, you can force the interpreter to re-import the module in this situation by using importlib.reload().
Using runpy.run_module() and runpy.run_path(), you can also run Python code interactively. Runpy is a module found in the Python Standard Library. Furthermore, run_module(), a function that enables you to run modules without importing them, can be found in this module. This function returns the global dictionary of the module that was executed.
In addition, the standard import mechanism is used to locate and execute the module in a fresh module namespace.
Moreover, the run_module() functions’ first argument must be a string with the name of the module without the .py extension.
Is running a Python script using the command-line easy?
Many lines of code can be written in Python interactive sessions, but everything you’ve written is lost once you close the session. Because of this, plain text files are typically used when writing Python programs. Those files will typically have the.py extension.
Furthermore, Python code files can be made using any plain text editor. Try PyScripter, a robust and user-friendly editor that will be covered in more detail later if you are new to Python programming.
Let’s first examine how to use the python command to run Python files. To do this, open a command line and press the enter key after typing “python” (or “python3” if you have both versions) and the path to your script:
$ python3 example.py
We get the expected output:
This is an example!
Furthermore, sometimes it’s useful to save the output of a script for later analysis. Here’s how you can do that:
$ python3 example.py > output.txt
Finally, if the file output.txt does not exist in the file system, it is made automatically. Contrary to this, if the file already exists in the system, then its contents will be overwritten with the new output.
Is it possible to run or use a Python script from a file manager?
Another way to run your Python scripts is by double-clicking the script’s icon in a file manager. Moreover, when you release your code for production, it might not be utilized frequently during the development phase.
However, before being able to run your scripts with a simple double-click, you must fulfill a few requirements. These requirements will vary depending on your operating system.
For instance, Windows links the programs python.exe and pythonw.exe with the file extensions .py and.pyw, respectively. By doing this, you can double-click on your scripts to run them.
You should be able to execute your scripts by double-clicking them in your file manager on Unix-like systems. Your script must have execution permissions to accomplish this.
You will likely only see the flash of a black window on your screen in either scenario when you have a script with a command-line interface.
How to use a Python script from an IDE or a text editor?
When creating larger and more complicated applications, you should use an advanced text editor or an integrated development environment (IDE).
These programs allow you to run your scripts directly from the environment. They frequently have a Run or Build command that can be accessed from the toolbar or the main menu. As was previously mentioned, PyScripter is one of your best options for this.
Embarcadero Delphi-based PyScripter aims to develop a Python IDE that can compete with the established Windows-based IDEs for other programming languages. PyScripter is a very helpful tool because it is compact, adaptable, and packed with features. Moreover, because it was designed from the ground up for Windows, it is noticeably quicker and more responsive than cumbersome text editors, all-purpose IDEs, or other Python cross-platform IDEs.
Moreover, code folding, brace highlighting, code completion, and syntax checking while you type are some of the many features of PyScripter. Additionally, Python source code tools make it easier for programmers to write code. A time-saving feature of PyScripter is the ability to drag and drop files from Explorer into this IDE. Moreover, PyScipter has great features like integrated debugging and unit testing.
Are you ready to run your Python scripts with PyScripter?
Running Python scripts and code is the first and most important skill you should learn if you want to get into the world of Python programming. It will be simpler for you to determine whether the code will work or not once you have a seat in the performance.
In addition to making managing your coding projects quick and easy, a good Python IDE like PyScripter also makes running those Python Scripts simple and hassle-free.