# First create an ArcGIS Pro Project, with at least one template, and put the
# name of it below.
import arcpy
TEMPLATE_NAME = "Square"
aprx = arcpy.mp.ArcGISProject("basic.aprx")
for lyt in aprx.listLayouts():
    if lyt.name == TEMPLATE_NAME:
        # export!
        print(f"  {lyt.name} ({lyt.pageHeight} x {lyt.pageWidth} {lyt.pageUnits})")
        lyt.exportToJPEG("out.jpg")