---
myst:
    substitutions:
        sentence:
            python: "[](#use_cases_module)"
            cpp: "the python version of this manual"
---
# Python version: greater than 3.8

From {{uranie}} version 4.9, only Python greater than 3.8 can be used due to the use of {{root}} 
version v6.32 (Python 2 is deprecated). Two words of caution about this:
              
- The macros provided in {{sentence[language]}} have indeed been tested with Python 3 (upper than 
3.8).

- Note, historically, from {{uranie}} version 4.5 to v4.8, both Python 2 and 3 were used at the same 
time if it is installed again a {{root}} version from v6.20.00 to v6.28.06. In order to get this 
compatibility, it means that the printing format has to be homogenised and this implies that from 
{{uranie}} version 4.2, these macros might not be working anymore for Python version below or equal 
to 2.6.

````{admonition} **Possible python configuration on a Linux OS**
When typing the following command on many present Linux OS

```bash
ls -l `which python`  && ls -l `which python3`
```

one can get these lines

```none
lrwxrwxrwx. 1 root root 9  8 févr.  2023 /usr/bin/python -> ./python3
lrwxrwxrwx. 1 root root 10  8 févr.  2023 /usr/bin/python3 -> python3.11
```
````

Today's operating systems usually embed both versions of python and many of these still use the 
version 2 as a reference (see the block above with both python versions). Given the fact that one can 
have as many different python versions as possible, it should be possible to specify which one is of 
interest for the ongoing installation. The following lines should be used to specify the python 
version to be used, providing that the "dev" packages are indeed installed for this version:

```bash
cmake ${PATH_TO_ROOT_SOURCES} -DPYTHON_EXECUTABLE=${PATH_TO_PYTHON_BIN} -DPYTHON_INCLUDE_DIR=${PATH_TO_PYTHON_INC}  -DPYTHON_LIBRARY=${PATH_TO_PYTHON_LIB} ...
```

These three specific python flags should be used both for {{root}} and {{uranie}} in a coherent way 
in order to install both platforms with a chosen Python's version. To get the recommended *cmake* 
line both for {{root}} and {{uranie}} see the README provided with the {{uranie}}-sources.