# Using Expression

It is possible to link some parameters to the data source via an expression.

To access this mode, click on the token icon next to a parameter to have access to the secondary menu.

<figure><img src="/files/CRk5USs1ksRdV9G1JU96" alt=""><figcaption></figcaption></figure>

From the secondary menu, choose the `Expression` option.&#x20;

There will be an indication next to the field for the parameter to indicate that this parameter is now in expression mode.

<figure><img src="/files/S8LoRRoekRGdffCfR5Kl" alt=""><figcaption></figcaption></figure>

Similar to above, you can directly like this parameter to a data source by clicking on the token icon and choosing your data source

<figure><img src="/files/wloGDgK2CgkoP3Zi2UQr" alt=""><figcaption></figcaption></figure>

After choosing the desired data source, you can click on the parameter field again and edit your expression

<figure><img src="/files/SF5QCP09W8LDKrHtGD9w" alt=""><figcaption></figcaption></figure>

From here, you are able to write simple python code to manipulate the data and how it is assigned to the parameter

<figure><img src="/files/fWZ6kWpUFSmcfi6tjwmg" alt=""><figcaption></figcaption></figure>


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