How do i create an importable file in python?
IntroductionIn Python, a module is a self-contained file with Python statements and definitions. For example, Show Modules help us break down large programs into small files that are more manageable. With modules, code reusability becomes a reality. Suppose we have a function that is frequently used in different programs. We can define this function in a module then import it into the various programs without having to copy its code each time. In this article, we will see how to create Python modules and how to use them in Python code. Writing ModulesA module is simply a Python file with the Let us begin by creating a function that simply prints "Hello World". To do this, create a new Python file and save it as
If you run the above code, it will return nothing. This is because we have not told the program to do anything. It is true that we have created a function named Now, move to the same directory where you have saved the above file and create a new file named
Output
The function was invoked successfully. We began by importing the module. The name of the file was Also, note the syntax that we have used to invoke the function. This is called the "dot notation", which allows us to call the function by first specifying the module name, and then the name of the function. However, that is just one way of importing the module and invoking the function. We could have done it as follows:
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In the above example, the first line commands the Python interpreter to import a function named However, in the case where our We can define a variable within a module, which can then be used by
other modules. To demonstrate this, open the file
Now, open the
Output
We have successfully invoked both the function and the variable defined in the module since we imported the whole module instead of just the We stated earlier that we can define a class within a module. Let's see how to do this in the next example. Open the
Here we have defined a class named Now, open the file
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In the script above, we again used the dot notation to create an object of the Although modules mostly consist of class definitions (in most cases), it is possible for them to actually run their own code as well when imported. To demonstrate this, let us
modify the
Now, open the file
Output
The above output shows that we defined and called the function within the module. When the module is imported, it directly returns the result from the function without having to invoke the function. This behavior isn't always desired, but it's helpful for certain use-cases, like pre-loading data from cache when the module is imported. Importing all Module ObjectsTo import all objects (functions, variables, classes, etc.) from a module, we can use the
After adding the above statement to a program, we will be able to use any function, variable, or
class contained in the Accessing a Module from Another PathIn Python, modules are used in more than one project. Hence, it makes no sense if you keep your modules in the directory of one of the projects, since other projects wouldn't be able to use it as easily. You have a couple of options whenever you need to access a module that is not stored in the same directory as your program. Let us discuss these in the next few sections: Appending PathsTo import a module from another path, you first need to import the The To demonstrate this, cut the Now, open the file
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In the above script, the line Adding a Module to Python PathThe above method works only if you import the Before doing anything else, you should first identify the path that Python searches for modules and packages. Just open the command line of your operating system and run the Import the
You can then run the following command to print out the path:
The output will contain at least one system path. If you do it from a programming environment, you will get several paths. In my case, I got the following:
Your goal should be to find the one in the environment that you are currently using. You should look for something like the following:
Move your
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ConclusionThis marks the end of this article. A module is simply a Python file with a set of variables and function definitions. A module facilitates code reusability since you can define a function in a module and invoke it from different programs instead of having to define the function in every program. Although a module is mostly used for function and class definitions, it may also export variables and class instances. How do you create a user defined module in Python?To create a module just save the code you want in a file with the file extension .py :. Save this code in a file named mymodule.py. ... . Import the module named mymodule, and call the greeting function: ... . Save this code in the file mymodule.py. ... . Import the module named mymodule, and access the person1 dictionary:. What makes a module of a package importable?We can import the functions, classes defined in a module to another module using the import statement in some other Python source file. When the interpreter encounters an import statement, it imports the module if the module is present in the search path.
How do I add an import path to Python?append() Function. This is the easiest way to import a Python module by adding the module path to the path variable. The path variable contains the directories Python interpreter looks in for finding modules that were imported in the source files.
What is __ init __ file in Python?The __init__.py files are required to make Python treat directories containing the file as packages. This prevents directories with a common name, such as string , unintentionally hiding valid modules that occur later on the module search path.
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