How to Check ‘pyasn1’ Package Version in Python?

In this article, I’ll show you:

💬 How to check the version of the Python module (package, library) pyasn1? And how to check if pyasn1 is installed anyways?

These are the eight best ways to check the installed version of the Python module pyasn1:

Method 1: pip show pyasn1
Method 2: pip list
Method 3: pip list | findstr pyasn1
Method 4: library.__version__
Method 5: importlib.metadata.version
Method 6: conda list
Method 7: pip freeze
Method 8: pip freeze | grep pyasn1

Before we go into these ways to check your pyasn1 version, let’s first quickly understand how versioning works in Python—you’ll be thankful to have spent a few seconds on this topic, believe me!

A Note on Python Version Numbering

💡Python versioning adds a unique identifier to different package versions using semantic versioning. Semantic versioning consists of three numerical units of versioning information in the format major.minor.patch.

In this tutorial, we’ll use the shorthand general version abbreviation like so:

x.y.z

Practical examples would use numerical values for x, y, and z:

1.2.3
4.1.4
1.0.0

This is shorthand for

major.minor.patch

Major releases (0.1.0 to 1.0.0) are used for the first stable release or “breaking changes”, i.e., major updates that break backward compatibility.
Minor releases (0.1.0 to 0.2.0) are used for larger bug fixes and new features that are backward compatible.
Patch releases (0.1.0 to 0.1.1) are used for smaller bug fixes that are backward compatible.

Let’s dive into the meat of this article:

💬 Question: How to check the (major, minor, patch) version of pyasn1 in your current Python environment?

Method 1: pip show

To check which version of the Python library pyasn1 is installed, run pip show pyasn1 or pip3 show pyasn1 in your CMD/Powershell (Windows), or terminal (macOS/Linux/Ubuntu).

This will work if your pip installation is version 1.3 or higher—which is likely to hold in your case because pip 1.3 was released a decade ago in 2013!!

Here’s an example in my Windows Powershell: I’ve highlighted the line that shows that my package version is a.b.c:

PS C:\Users\xcent> pip show pyasn1
Name: pyasn1
Version: a.b.c
Summary: ...
Home-page: ...
Author: ...
Author-email: ...
License: ...
Location: ...
Requires: ...
Required-by: ...

In some instances, this will not work—depending on your environment. In this case, try those commands before giving up:

python -m pip show pyasn1
python3 -m pip show pyasn1
py -m pip show pyasn1
pip3 show pyasn1

Next, we’ll dive into more ways to check your pyasn1 version.

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Method 2: pip list

To check the versions of all installed packages, use pip list and locate the version of pyasn1 in the output list of package versions sorted alphabetically.

This will work if your pip installation is version 1.3 or higher.

Here’s a simplified example for Windows Powershell, I’ve highlighted the line that shows the package version is 1.2.3:

PS C:\Users\xcent> pip list
Package         Version
--------------- ---------
aaa             1.2.3
...
pyasn1             1.2.3
...
zzz             1.2.3

In some instances, this will not work—depending on your environment. Then try those commands before giving up:

python -m pip list
python3 -m pip list
py -m pip list
pip3 list

Method 3: pip list + findstr on Windows

To check the versions of a single package on Windows, you can chain pip list with findstr pyasn1 using the CMD or Powershell command: pip3 list | findstr pyasn1 to locate the version of pyasn1 in the output list of package versions automatically.

Here’s an example for pyasn1:

pip3 list | findstr pyasn1

1.2.3

Method 4: Module version Attribute

To check which version is installed of a given library, you can use the library.__version__ attribute after importing the library (package, module) with import library.

Here’s the code:

import my_library
print(my_library.__version__)
# x.y.z for your version output

Here’s an excerpt from the PEP 8 docs mentioning the __version__ attribute.

“PEP 8 describes the use of a module attribute called __version__ for recording “Subversion, CVS, or RCS” version strings using keyword expansion. In the PEP author’s own email archives, the earliest example of the use of an __version__ module attribute by independent module developers dates back to 1995.”

You can also use the following one-liner snippet to run this from your terminal (macOS, Linux, Ubuntu) or CMD/Powershell (Windows):

python3 -c "import my_library; print(my_library.__version__)"

However, this method doesn’t work for all libraries, so while simple, I don’t recommend it as a general approach for that reason.

Method 5: importlib.metadata.version

The importlib.metadata library provides a general way to check the package version in your Python script via importlib.metadata.version('pyasn1') for library pyasn1. This returns a string representation of the specific version such as 1.2.3 depending on the concrete version in your environment.

Here’s the code:

import importlib.metadata
print(importlib.metadata.version('pyasn1'))
# 1.2.3

Method 6: conda list

If you have created your Python environment with Anaconda, you can use conda list to list all packages installed in your (virtual) environment. Optionally, you can add a regular expression using the syntax conda list regex to list only packages matching a certain pattern.

How to list all packages in the current environment?

conda list

How to list all packages installed into the environment 'xyz'?

conda list -n xyz

Regex: How to list all packages starting with 'pyasn1'?

conda list '^pyasn1'

Method 7: pip freeze

The pip freeze command without any option lists all installed Python packages in your environment in alphabetically order (ignoring UPPERCASE or lowercase). You can spot your specific package pyasn1 if it is installed in the environment.

pip freeze

Output example (depending on your concrete environment/installation):

PS C:\Users\xcent> pip freeze
aaa==1.2.3
...
pyasn1==1.2.3
...
zzz==1.2.3

You can modify or exclude specific packages using the options provided in this screenshot:

Method 8: pip freeze + grep on Linux/Ubuntu/macOS

To check the versions of a single package on Linux/Ubuntu/macOS, you can chain pip freeze with grep pyasn1 using the CMD or Powershell command: pip freeze | grep pyasn1 to programmatically locate the version of your particular package pyasn1 in the output list of package versions.

Here’s an example for pyasn1:

pip freeze | grep pyasn1
pyasn1==1.2.3

Related Questions

Check pyasn1 Installed Python

How to check if pyasn1 is installed in your Python script?

To check if pyasn1 is installed in your Python script, you can run import pyasn1 in your Python shell and surround it by a try/except to catch a potential ModuleNotFoundError.

try:
    import pyasn1
    print("Module pyasn1 installed")
except ModuleNotFoundError:
    print("Module pyasn1 not installed")

Check pyasn1 Version Python

How to check the package version of pyasn1 in Python?

To check which version of pyasn1 is installed, use pip show pyasn1 or pip3 show pyasn1 in your CMD/Powershell (Windows), or terminal (macOS/Linux/Ubuntu) to obtain the output major.minor.patch.

pip show pyasn1  # or pip3 show pyasn1
# 1.2.3

Check pyasn1 Version Linux

How to check my pyasn1 version in Linux?

To check which version of pyasn1 is installed, use pip show pyasn1 or pip3 show pyasn1 in your Linux terminal.

pip show pyasn1  # or pip3 show pyasn1
# 1.2.3

Check pyasn1 Version Ubuntu

How to check my pyasn1 version in Ubuntu?

To check which version of pyasn1 is installed, use pip show pyasn1 or pip3 show pyasn1 in your Ubuntu terminal.

pip show pyasn1  # or pip3 show pyasn1
# 1.2.3

Check pyasn1 Version Windows

How to check my pyasn1 version on Windows?

To check which version of pyasn1 is installed, use pip show pyasn1 or pip3 show pyasn1 in your Windows CMD, command line, or PowerShell.

pip show pyasn1  # or pip3 show pyasn1
# 1.2.3

Check pyasn1 Version Mac

How to check my pyasn1 version on macOS?

To check which version of pyasn1 is installed, use pip show pyasn1 or pip3 show pyasn1 in your macOS terminal.

pip show pyasn1  # or pip3 show pyasn1
# 1.2.3

Check pyasn1 Version Jupyter Notebook

How to check my pyasn1 version in my Jupyter Notebook?

To check which version of pyasn1 is installed, add the line !pip show pyasn1 to your notebook cell where you want to check. Notice the exclamation mark prefix ! that allows you to run commands in your Python script cell.

!pip show pyasn1

Output: The following is an example on how this looks for pyasn1 in a Jupyter Notebook cell:

Package         Version
--------------- ---------
aaa             1.2.3
...
pyasn1             1.2.3
...
zzz             1.2.3

Check pyasn1 Version Conda/Anaconda

How to check the pyasn1 version in my conda installation?

Use conda list 'pyasn1' to list version information about the specific package installed in your (virtual) environment.

conda list 'pyasn1'

Check pyasn1 Version with PIP

How to check the pyasn1 version with pip?

You can use multiple commands to check the pyasn1 version with PIP such as pip show pyasn1, pip list, pip freeze, and pip list.

pip show pyasn1
pip list
pip freeze
pip list

The former will output the specific version of pyasn1. The remaining will output the version information of all installed packages and you have to locate pyasn1 first.

Check Package Version in VSCode or PyCharm

How to check the pyasn1 version in VSCode or PyCharm?

Integrated Development Environments (IDEs) such as VSCode or PyCharm provide a built-in terminal where you can run pip show pyasn1 to check the current version of pyasn1 in the specific environment you’re running the command in.

pip show pyasn1
pip3 show pyasn1

pip list
pip3 list

pip freeze
pip3 freeze

You can type any of those commands in your IDE terminal like so:

Summary

In this article, you’ve learned those best ways to check a Python package version:

Method 1: pip show pyasn1
Method 2: pip list
Method 3: pip list | findstr pyasn1
Method 4: library.__version__
Method 5: importlib.metadata.version
Method 6: conda list
Method 7: pip freeze
Method 8: pip freeze | grep pyasn1

Thanks for giving us your valued attention — we’re grateful to have you here! 🙂

Programmer Humor

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~~~

There are 10 types of people in the world. Those who understand trinary, those who don’t, and those who mistake it for binary.
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