Listing layers from .mxd file using ArcPy for ArcGIS Pro?

I am looking for a way to access a .mxd file's layer names and data sources.

In ArcGIS Desktop, I could do:

def print_layer_info(mxd_path):
    print(mxd_path + ":")
    mxd = arcpy.mapping.MapDocument(mxd_path)


    for df in arcpy.mapping.ListDataFrames(mxd, "*"):
        lyr = arcpy.mapping.ListLayers(mxd, "", df)[0]
        if lyr.supports("dataSource"):
            print "\t" + lyr.name
            print "\t\t" + lyr.dataSource
    del mxd

According to http://pro.arcgis.com/en/pro-app/arcpy/mapping/migratingfrom10xarcpymapping.htm, I could do:

p = arcpy.mp.ArcGISProject("file.mxd")

But that doesn't work. When I do that I get a OSError.

Since the arcpy.mapping.MapDocument is gone in ArcPy for ArcGIS Pro, what is the equivalent way of reading layer name and datasource of an .mxd file?