input: Write a function to create a BPMN diagram for FOMDES process 1 using Python and the bpmn_pgv library. The diagram should include clusters for Secretaría Ejecutiva, Presidencia, and Presupuesto/Administración, with specific tasks and edges defined within each cluster. Additionally, include nodes for SIGEFOMDES Administración and SISAC, and connect them to the appropriate clusters using dashed edges. Finally, save the diagram as a PNG file named "proc4.png" and a DOT file named "proc4.dot".
  
  assert create_bpmn_diagram("FOMDES process 1")
  assert create_bpmn_diagram("Another process")
  assert create_bpmn_diagram("Test process")
output: def create_bpmn_diagram(process_name):
      import bpmn_pgv as bpmn
  
      g = bpmn.BPMN()
  
      # Clusters
      secretaria = g.add_cluster("Secretaría Ejecutiva")
      presidencia = g.add_cluster("Presidencia")
      presupuesto = g.add_cluster("Presupuesto/Administración")
  
      # Tasks within clusters
      task1 = g.add_task("Task 1", cluster=secretaria)
      task2 = g.add_task("Task 2", cluster=presidencia)
      task3 = g.add_task("Task 3", cluster=presupuesto)
  
      # Nodes
      sigefomdes = g.add_node("SIGEFOMDES Administración")
      sisac = g.add_node("SISAC")
  
      # Edges
      g.add_edge(task1, task2)
      g.add_edge(task2, task3)
      g.add_edge(sigefomdes, secretaria, style="dashed")
      g.add_edge(sisac, presidencia, style="dashed")
  
      # Save diagram
      g.write_png("proc4.png")
      g.write_dot("proc4.dot")
  
      return True