code: def _nextpow2(i):
      """Find next power of 2."""
      n = 1
      while n < i:
          n *= 2
      return n
  
imports: import numpy
  from sklearn.base import BaseEstimator, TransformerMixin
  from sklearn.covariance import shrunk_covariance
  from sklearn.metrics.pairwise import pairwise_kernels
  from .spatialfilters import Xdawn
  from .utils.covariance import covariances, covariances_EP, cospectrum, coherence, block_covariances
label_desc: Use image node_id 1 for calling a global function with example usage: _nextpow2(i) and returns: n