# Overview
The LAMMPS distribution includes a `python` directory with the Python
code needed to run LAMMPS from Python. The `python/lammps` package
contains [the \"lammps\" Python module](Python_module) that wraps the
LAMMPS C-library interface. This module makes it is possible to do the
following either from a Python script, or interactively from a Python
prompt:
- create one or more instances of LAMMPS
- invoke LAMMPS commands or read them from an input script
- run LAMMPS incrementally
- extract LAMMPS results
- and modify internal LAMMPS data structures.
From a Python script you can do this in serial or in parallel. Running
Python interactively in parallel does not generally work, unless you
have a version of Python that extends Python to enable multiple
instances of Python to read what you type.
To do all of this, you must build LAMMPS in [\"shared\" mode](exe) and
make certain that your Python interpreter can find the `lammps` Python
package and the LAMMPS shared library file.
The Python wrapper for LAMMPS uses the
[ctypes](https://docs.python.org/3/library/ctypes.html)\_ package in
Python, which auto-generates the interface code needed between Python
and a set of C-style library functions. Ctypes has been part of the
standard Python distribution since version 2.5. You can check which
version of Python you have by simply typing \"python\" at a shell
prompt. Below is an example output for Python version 3.8.5.
``` console
$ python
Python 3.8.5 (default, Aug 12 2020, 00:00:00)
[GCC 10.2.1 20200723 (Red Hat 10.2.1-1)] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>>
```
:::: warning
::: title
Warning
:::
The options described in this section of the manual for using Python
with LAMMPS currently support either Python 2 or 3. Specifically version
2.7 or later and 3.6 or later. Since the Python community no longer
maintains Python 2 (see [this
notice](https://www.python.org/doc/sunset-python-2/)\_), we recommend
use of Python 3 with LAMMPS. While Python 2 code should continue to
work, that is not something we can guarantee long-term. If you notice
Python code in the LAMMPS distribution that is not compatible with
Python 3, please contact the LAMMPS developers or submit [and issue on
GitHub](https://github.com/lammps/lammps/issues)\_
::::
------------------------------------------------------------------------
LAMMPS can work together with Python in three ways. First, Python can
wrap LAMMPS through the its [library interface](Library), so that a
Python script can create one or more instances of LAMMPS and launch one
or more simulations. In Python terms, this is referred to as
\"extending\" Python with a LAMMPS module.
Launching LAMMPS via Python
Second, the lower-level Python interface in the `lammps Python
class `{.interpreted-text role="py:class"}\_\_ can be
used indirectly through the provided
`PyLammps `{.interpreted-text role="py:class"}\_\_ and
`IPyLammps `{.interpreted-text role="py:class"}\_\_
wrapper classes, also written in Python. These wrappers try to simplify
the usage of LAMMPS in Python by providing a more object-based interface
to common LAMMPS functionality. They also reduce the amount of code
necessary to parameterize LAMMPS scripts through Python and make
variables and computes directly accessible.
Using the PyLammps / IPyLammps wrappers
Third, LAMMPS can use the Python interpreter, so that a LAMMPS input
script or styles can invoke Python code directly, and pass information
back-and-forth between the input script and Python functions you write.
This Python code can also call back to LAMMPS to query or change its
attributes through the LAMMPS Python module mentioned above. In Python
terms, this is called \"embedding\" Python into LAMMPS. When used in
this mode, Python can perform script operations that the simple LAMMPS
input script syntax can not.
Calling Python code from LAMMPS
