how_to_sanitize_a_blend

how_to_sanitize_a_blend.py

import bpy

#unselect everything
# <insert code here, this can vary depending on your situation> 
# bpy.ops.object.select_all()

# gather list of items of interest.
candidate_list = [item.name for item in bpy.data.objects if item.type == "MESH"]

# select them only.
for object_name in candidate_list:
  bpy.data.objects[object_name].select = True

# remove all selected.
bpy.ops.object.delete()

# remove the meshes, they have no users anymore.
for item in bpy.data.meshes:
  bpy.data.meshes.remove(item)