Show all functions in module python

Question

For global functions dir() is the command to use (as mentioned in most of these answers), however this lists both public functions and non-public functions together.

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List All Functions of a Python Module
Method 1: Using the dir() Function:
Method 2: Using Inspect Module:
How do I list all functions in a Python module?
How do I display the contents of a Python module?
Which library function returns the list of all functions in a module?
How do I see all methods in Python?

For example running:

>>> import re
>>> dir(re)

Returns functions/classes like:

'__all__', '_MAXCACHE', '_alphanum_bytes', '_alphanum_str', '_pattern_type', '_pickle', '_subx'

Some of which are not generally meant for general programming use (but by the module itself, except in the case of DunderAliases like __doc__, __file__ ect). For this reason it may not be useful to list them with the public ones (this is how Python knows what to get when using from module import *).

__all__ could be used to solve this problem, it returns a list of all the public functions and classes in a module (those that do not start with underscores - _). See Can someone explain __all__ in Python? for the use of __all__.

Here is an example:

>>> import re
>>> re.__all__
['match', 'fullmatch', 'search', 'sub', 'subn', 'split', 'findall', 'finditer', 'compile', 'purge', 'template', 'escape', 'error', 'A', 'I', 'L', 'M', 'S', 'X', 'U', 'ASCII', 'IGNORECASE', 'LOCALE', 'MULTILINE', 'DOTALL', 'VERBOSE', 'UNICODE']
>>>

All the functions and classes with underscores have been removed, leaving only those that are defined as public and can therefore be used via import *.

Note that __all__ is not always defined. If it is not included then an AttributeError is raised.

A case of this is with the ast module:

>>> import ast
>>> ast.__all__
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: module 'ast' has no attribute '__all__'
>>>

We all must be familiar with the Python Modules and how they work, and we also must be aware that how we can use Python Modules inside a program to use some particular functions. Sometimes many of us wonder how many functions are present in the Python Modules which we have installed in our system. This is a common question that normally comes into everyone's mind while using a particular, and answering this question is not as complex as it looks.

There can be multiple functions present inside a Python Module depending upon the size and functionality of the module. If we go and read the documentation regarding every particular module of Python to find out how many functions are present inside Python Modules, then it will be going to take a lot of effort from us and will waste our time. Therefore, there must be some other ways through which we can find out whether how many functions are inside a Python Module, and we are going to learn about these methods in this tutorial. We will learn the ways in this tutorial through which we can easily find out how many functions there are in a given Python Module.

List All Functions of a Python Module

Before we learn about the methods from which we can list down all the functions present in a Python module, we have to understand where and why we need to know how many functions are present in the module. Answering this question not only will solve the doubt which is coming to mind of most of us, but it will also make us keener for learning the methods. Therefore, first, we will see the reasons that are given below, for which we need to check out the functions present in a Python module:

Sometimes, we have to check the module which is installed in our system has all the functions which we require to perform a specific task or a task for which we have installed the system.
Many times, we don't want to update the module installed in our system, and therefore we have to look that all the functions which are required to us are present in the current version or not.
Other than this, sometimes we don't know how many different types of functions are present in a module, and we want to know about all of these functions present in a Python module.

These are the main reasons for which one thinks of checking all the functions present in a Python module, but there can be other reasons too that depend from person to person. Now, we will talk about the methods from which we can check the list of all the functions present in a Python module.

Following are the methods which will help us in looking for all the functions present in a Python module:

By dir() method
By Inspect module

Now, we will learn about both methods and find out how we can implement this method to list down all the functions from a Python module.

Method 1: Using the dir() Function:

We can list down all the functions present in a Python module by simply using the dir() method in the Python shell or in the command prompt shell. We have first to import the module in the Python shell, and then we have to write the module name in the dir() method, and it will return the list of all functions present in a particular Python module. Let's understand the implementation of this method through the following example program.

Example 1:

Look at the following Python program where we have used the statistics module in the dir() function:

Output:

['Counter', 'Decimal', 'Fraction', 'NormalDist', 'StatisticsError', '__all__', '__builtins__', ????, 'quantiles', 'random', 'sqrt', 'stdev', 'tau', 'variance']

As we can see, when we have used the statistics module inside the dir() method after importing it in the Python shell, the Python shell has listed all the functions present in the statistics module.

Method 2: Using Inspect Module:

In this method, we will use isfunction and getmembers function from the inspect module (A build-in module of Python) to list down all the functions present in a Python module. We will loop over the module which functions we want to list out using the for loop. One thing we should note here is that we can't list out functions of built-in modules of Python using this method as the type of functions present in any built-in module is not considered as a function for the inspect module. Let's understand the implementation of this method through the following example:

Example 2:

Look at the following Python program where we have used the Numpy module inside the inspect module's functions:

Output:

['ALLOW_THREADS', 'AxisError', 'BUFSIZE', 'CLIP', 'ComplexWarning', 'DataSource', 'ERR_CALL', 'ERR_DEFAULT', 'ERR_IGNORE', ???., 'version', 'void', 'void0', 'vsplit', 'vstack', 'warnings', 'where', 'who', 'zeros', 'zeros_like']

As we can see, that Python shell has listed all the functions present in the numpy module.

How do I list all functions in a Python module?

We can list down all the functions present in a Python module by simply using the dir() method in the Python shell or in the command prompt shell.

How do I display the contents of a Python module?

We've then used the dir () function to display the attributes provided by the module. Here is a brief description of the attributes: Bye, Welcome – the functions provided by the module. __builtins__ – a listing of all the built-in attributes that are accessible from the module.

Which library function returns the list of all functions in a module?

The dir() function The dir() built-in function returns a sorted list of strings containing the names defined by a module. The list contains the names of all the modules, variables, and functions that are defined in a module.

How do I see all methods in Python?

You can use the built in dir() function to get a list of all the attributes a module has. Try this at the command line to see how it works. Also, you can use the hasattr(module_name, "attr_name") function to find out if a module has a specific attribute. See the Guide to Python introspection for more information.

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