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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 sampleCellsAcrossColumns(numCellPairs, cellsPerColumn, numColumns, seed=42):
 """ Generate indices of cell pairs, each pair of cells are from different column @return cellPairs (list) list of cell pairs """

  np.random.seed(seed)
  cellPairs = []
  for i in range(numCellPairs):
    randCols = np.random.choice(np.arange(numColumns), (2, ), replace=False)
    randCells = np.random.choice(np.arange(cellsPerColumn), (2, ), replace=False)

    cellsPair = np.zeros((2, ))
    for j in range(2):
      cellsPair[j] = randCols[j] * cellsPerColumn + randCells[j]
    cellPairs.append(cellsPair.astype('int32'))
  return cellPairs