input: Write a function to find the maximum value within a nested dictionary. If the dictionary is empty or contains no numeric values, return None. The function should recursively search through all nested dictionaries to find the maximum value.
  
  def findMaxValue(dict):
      max_val = None
      for key, value in dict.items():
          if isinstance(value, dict):
              max_val = max(findMaxValue(value), max_val)
          else:
              max_val = max(value, max_val)
      return max_val
output: def findMaxValue(dict):
      max_val = None
      for key, value in dict.items():
          if isinstance(value, dict):
              nested_max = findMaxValue(value)
              if nested_max is not None:
                  if max_val is None:
                      max_val = nested_max
                  else:
                      max_val = max(max_val, nested_max)
          elif isinstance(value, (int, float)):
              if max_val is None:
                  max_val = value
              else:
                  max_val = max(max_val, value)
      return max_val