code: def poly2cheb(pol):
      """
      Convert a polynomial to a Chebyshev series.
  
      Convert an array representing the coefficients of a polynomial (relative
      to the "standard" basis) ordered from lowest degree to highest, to an
      array of the coefficients of the equivalent Chebyshev series, ordered
      from lowest to highest degree.
  
      Parameters
      ----------
      pol : array_like
          1-D array containing the polynomial coefficients
  
      Returns
      -------
      c : ndarray
          1-D array containing the coefficients of the equivalent Chebyshev
          series.
  
      See Also
      --------
      cheb2poly
  
      Notes
      -----
      The easy way to do conversions between polynomial basis sets
      is to use the convert method of a class instance.
  
      Examples
      --------
      >>> from numpy import polynomial as P
      >>> p = P.Polynomial(range(4))
      >>> p
      Polynomial([0., 1., 2., 3.], domain=[-1,  1], window=[-1,  1], symbol='x')
      >>> c = p.convert(kind=P.Chebyshev)
      >>> c
      Chebyshev([1.  , 3.25, 1.  , 0.75], domain=[-1.,  1.], window=[-1., ...
      >>> P.chebyshev.poly2cheb(range(4))
      array([1.  , 3.25, 1.  , 0.75])
  
      """
      [pol] = pu.as_series([pol])
      deg = len(pol) - 1
      res = 0
      for i in range(deg, -1, -1):
          res = chebadd(chebmulx(res), pol[i])
      return res
  
imports: import numpy
  import numpy.linalg
  from numpy.lib.array_utils import normalize_axis_index
  from .None import polyutils
  from ._polybase import ABCPolyBase
label_desc: Use image node_id 7 for calling a global function with example usage: poly2cheb(pol) and returns: res