code: def _augknt(x, k):
      """Construct a knot vector appropriate for the order-k interpolation."""
      return np.r_[(x[0],) * k, x, (x[-1],) * k]
  
imports: import operator
  import numpy
  from numpy.core.multiarray import normalize_axis_index
  from scipy.linalg import get_lapack_funcs, LinAlgError, cholesky_banded, cho_solve_banded, solve, solve_banded
  from .None import _bspl
  from .None import _fitpack_impl
  from .None import _fitpack
  from scipy._lib._util import prod
label_desc: Use image node_id 4 for calling a global function with example usage: _augknt(x, k) and returns: np