code: def __init__(self, L, width=None, dtype=None):
      global np
      import numpy as np
  
      (n, n) = L.shape
      self.dtype = dtype
      self.n = n
      if width is None:
          self.w = self.width(L)
      else:
          self.w = width
      self.C = np.zeros((self.w, n), dtype=dtype)
      self.L1 = L[1:, 1:]
      self.init_solver(L)
  
imports: import networkx
label_desc: Use image node_id 1 to create a new InverseLaplacian object  with example: obj = InverseLaplacian(L, width, dtype)