| #mission by ruu
import bpy
import bmesh
def select_vertices():
    """ select every vertex of the current object which has exactly 4 edges.
    """
    bpy.ops.object.mode_set(mode='EDIT')
    obj = bpy.context.active_object
    bm = bmesh.from_edit_mesh(obj.data)
    for v in bm.verts:
        if 4==len(v.link_edges):
            v.select = True
            print(v)
    bmesh.update_edit_mesh(obj.data)
#
select_vertices()
 | 
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