code: def gram_linear(x):
      """Compute Gram (kernel) matrix for a linear kernel.
  
      Args:
        x: A num_examples x num_features matrix of features.
  
      Returns:
        A num_examples x num_examples Gram matrix of examples.
      """
      return x.dot(x.T)
  
imports: import numpy
label_desc: Use image node_id 1 for calling a global function with example usage: gram_linear(x) and returns: x