# SYS\_PATH\_CONF

The `SYS_PATH_CONF` configuration allows you explicitly specify which paths you want to include in your project's `sys.path`. Doing so can allow users to import modules and packages from sources outside of their direct project. 

If this option is not specified, Prism throws a warning and automatically adds the project directory

To see why this is useful, suppose you had the following directory structure:

```
all_prism_projects/
  |- prism_project_1/
    |- prism_project.py
    |- tasks/...
    |- utils1.py
  |- prism_project_2/
    |- prism_project.py
    |- tasks/...
    |- utils2.py
  |- prism_project_2/
    |- prism_project.py
    |- tasks/..
    |- utils2.py
  |- common_utils.py
```

By default, each project directory is added to each Prism project's `sys.path` at runtime. That means that `prism_project_1` can access `utils1.py`, `prism_project_2` can access `utils2.py`, and so on. However, the parent directory (i.e., `all_prism_projects/`)  is not added to the project's `sys.path` by default, so `common_utils.py` would not be accessible to any of the projects.

This can easily be remedied with `SYS_PATH_CONF`. For example: 

```python
# all_prism_projects/prism_project_1/prism_project.py

...
SYS_PATH_CONF = [
    Path(__file__).parent,
    Path(__file__).parent.parent # added the parent path!
]
...
```

Now, a module in `prism_project_1` can import `common_utils` at runtime:

```python
# all_prism_projects/prism_project_1/tasks/example_module.py

import prism_project    # this is OK since project directory is in sys.path
import common_utils     # this is OK since all_prism_projects/ is in sys.path
import prism.task

class ExampleTask(prism.task.PrismTask)
    ...
```

{% hint style="info" %}
**Important:** we recommend specifying paths as *relative paths* rather than absolute paths (i.e., hard-coded string paths). This enables reproducibility across different machines.
{% endhint %}

More information on `sys.path` can be found [here](https://docs.python.org/3/library/sys.html).