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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def createL4L2Column(network, networkConfig, suffix=""):
 """ Create a a single column containing one L4 and one L2. networkConfig is a dict that must contain the following keys (additional keys ok):
 { "enableFeedback": True, "externalInputSize": 1024, "sensorInputSize": 1024, "L4RegionType": "py.ApicalTMPairRegion", "L4Params": { <constructor parameters for the L4 region> }, "L2Params": { <constructor parameters for ColumnPoolerRegion> }, "lateralSPParams": { <constructor parameters for optional SPRegion> }, "feedForwardSPParams": { <constructor parameters for optional SPRegion> } } Region names are externalInput, sensorInput, L4Column, and ColumnPoolerRegion. Each name has an optional string suffix appended to it. Configuration options: "lateralSPParams" and "feedForwardSPParams" are optional. If included appropriate spatial pooler regions will be added to the network. If externalInputSize is 0, the externalInput sensor (and SP if appropriate) will NOT be created. In this case it is expected that L4 is a sequence memory region (e.g. ApicalTMSequenceRegion) """


  externalInputName = "externalInput" + suffix
  sensorInputName = "sensorInput" + suffix
  L4ColumnName = "L4Column" + suffix
  L2ColumnName = "L2Column" + suffix

  L4Params = copy.deepcopy(networkConfig["L4Params"])
  L4Params["basalInputWidth"] = networkConfig["externalInputSize"]
  L4Params["apicalInputWidth"] = networkConfig["L2Params"]["cellCount"]

  if networkConfig["externalInputSize"] > 0:
    network.addRegion(
      externalInputName, "py.RawSensor",
      json.dumps({"outputWidth": networkConfig["externalInputSize"]}))
  network.addRegion(
    sensorInputName, "py.RawSensor",
    json.dumps({"outputWidth": networkConfig["sensorInputSize"]}))

  # Fixup network to include SP, if defined in networkConfig
  if networkConfig["externalInputSize"] > 0:
    _addLateralSPRegion(network, networkConfig, suffix)
  _addFeedForwardSPRegion(network, networkConfig, suffix)

  network.addRegion(
    L4ColumnName, networkConfig["L4RegionType"],
    json.dumps(L4Params))
  network.addRegion(
    L2ColumnName, "py.ColumnPoolerRegion",
    json.dumps(networkConfig["L2Params"]))

  # Set phases appropriately so regions are executed in the proper sequence
  # This is required when we create multiple columns - the order of execution
  # is not the same as the order of region creation.
  if networkConfig["externalInputSize"] > 0:
    network.setPhases(externalInputName,[0])
  network.setPhases(sensorInputName,[0])

  _setLateralSPPhases(network, networkConfig)
  _setFeedForwardSPPhases(network, networkConfig)

  # L4 and L2 regions always have phases 2 and 3, respectively
  network.setPhases(L4ColumnName,[2])
  network.setPhases(L2ColumnName,[3])

  # Link SP region(s), if applicable
  if networkConfig["externalInputSize"] > 0:
    _linkLateralSPRegion(network, networkConfig, externalInputName, L4ColumnName)
  _linkFeedForwardSPRegion(network, networkConfig, sensorInputName, L4ColumnName)

  # Link L4 to L2
  network.link(L4ColumnName, L2ColumnName, "UniformLink", "",
               srcOutput="activeCells", destInput="feedforwardInput")
  network.link(L4ColumnName, L2ColumnName, "UniformLink", "",
               srcOutput="predictedActiveCells",
               destInput="feedforwardGrowthCandidates")

  # Link L2 feedback to L4
  if networkConfig.get("enableFeedback", True):
    network.link(L2ColumnName, L4ColumnName, "UniformLink", "",
                 srcOutput="feedForwardOutput", destInput="apicalInput",
                 propagationDelay=1)

  # Link reset output to L2 and L4
  network.link(sensorInputName, L2ColumnName, "UniformLink", "",
               srcOutput="resetOut", destInput="resetIn")
  network.link(sensorInputName, L4ColumnName, "UniformLink", "",
               srcOutput="resetOut", destInput="resetIn")

  enableProfiling(network)

  return network