Importerror dynamic module does not define module export function

One of the most common errors we encounter is “ImportError: dynamic module does not define module export function“.

So, this article aims to explain what this error means and how to fix it.

Importerror dynamic module does not define module export function

The “ImportError: dynamic module does not define module export function” error occurs when you try to import a module that was compiled as a shared library.

However, the shared library does not contain the expected symbol (function or variable) that the module is trying to import.

In simpler terms, the Python interpreter is trying to load a module that was compiled separately (as a shared library).

But the shared library does not have the function or variable that the module is expecting to use.

Solutions – Importerror dynamic module does not define module export function

After we understand this error, the following are the solutions to resolve the error.

Rebuild the shared library

If the shared library was not compiled correctly, you may need to rebuild it with the correct flags or options. Depending on the language used to compile the library, the commands may differ.

Here are some examples:

For C or C++: gcc -shared -o mylib.so mylib.c
For Fortran: gfortran -shared -o mylib.so mylib.f90
For Rust: rustc --crate-type=cdylib mylib.rs

Check the library path

Make sure that the directory containing the shared library is in the library path (LD_LIBRARY_PATH).

This can be done by setting the environment variable using the following command:

For Linux/MacOS: export LD_LIBRARY_PATH=/path/to/shared/library:$LD_LIBRARY_PATH
For Windows: setx PATH "C:\path\to\shared\library;%PATH%"

Check the library dependencies

If the shared library depends on other libraries, make sure that they are installed and in the library path.

You can use the ldd command on Linux/MacOS or Dependency Walker on Windows to check the dependencies.

Check the module version

If the module was compiled against a different version of the shared library, you may need to recompile the module or update the shared library to the correct version.

Check the function or variable name

Make sure that the function or variable that the module is trying to import is defined in the shared library and has the correct name.

Remember these are some general solutions that may help resolve the error. The specific commands may vary depending on your operating system and the language used to compile the shared library.

Anyway, here are other fixed errors you can consider when somehow you might encounter them.

• cannot import name ‘safe_str_cmp’ from ‘werkzeug.security’
• importerror: cannot import name ‘legacyversion’ from ‘packaging.version’

Conclusion

In conclusion, this error Importerror dynamic module does not define module export function occurs when a dynamic module is imported, but it does not define a module export function.

The error can be caused by several reasons, including missing module export function in dynamic module and incorrect usage of module export function.

To fix this error, you need to ensure that the dynamic module defines a module export function and that it is used correctly.

I think that’s all for this. I hope this article has helped you fix the error.

Until next time! 😊

Python ImportError debugging checklist

• Read the full error message. It names the module AND the missing symbol.
• Check the library version. Most ImportErrors come from a symbol that was renamed or removed.
• Search the release notes. Most libraries document renamed symbols.
• Rule out typos. Case-sensitive. from collections import deque not Deque.
• Rule out circular imports. Move the import inside the function or use TYPE_CHECKING.

ImportError vs ModuleNotFoundError

• ModuleNotFoundError: the module itself does not exist (usually not installed).
• ImportError: the module exists but the symbol you asked for does not (or a circular import fires).
• Both inherit from ImportError, so except ImportError catches both.

Common patterns

# Defensive import with fallback
try:
    from cchardet import detect
except ImportError:
    from chardet import detect  # pure-Python fallback

# Runtime check for optional dependency
def read_excel(path):
    try:
        import openpyxl
    except ImportError:
        raise ImportError("openpyxl is required for Excel support: pip install openpyxl")
    ...

Modern tooling to prevent ImportError

• Pin versions in requirements.txt or pyproject.toml.
• Use uv or Poetry. Modern package managers with reproducible installs.
• Use mypy or Pyright. Catches ImportError-adjacent bugs at type-check time.
• Test in CI. Fresh install + full test suite catches missing deps and version drift.

Glay Eliver

Programmer & Technical Writer at PIES IT Solution

Glay Eliver is a programmer and writer at PIES IT Solution, author of over 600 tutorials at itsourcecode.com. Specializes in JavaScript tutorials, Microsoft Office how-tos (Excel, Word, PowerPoint), and Python error debugging covering ImportError, TypeError, AttributeError, ModuleNotFoundError, and JavaScript ReferenceError. Authored several of the site’s highest-traffic Excel and MS Office reference articles.

Expertise: JavaScript · MS Excel · MS Word · MS PowerPoint · Python · Python ImportError · Python TypeError · Python AttributeError · ModuleNotFoundError · JavaScript ReferenceError · Pygame
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