Want to add the flow direction (spatial analyst tool) functionality in my custom tool

[QaziAshiqueEMowla]

I am building a tool to do some post-processing on two raster files that I will be providing as inputs. One of the internal calculations I want in my code is applying the flow direction (spatial analyst tool) analysis on one of the rasters. I want the flow direction type as DINF. 

However I cannot figure out how to incorporate the functionality of a built-in tool in this custom-made tool. Is it even possible? 

[DanPatterson · Accepted solution]

code examples are shown in the help topic

Flow Direction (Spatial Analyst)—ArcGIS Pro | Documentation

you would have to have arcpy on the machine and access to a spatial analyst license