code: def manhattan(x, y):
      """
      Compute the Manhattan distance between between two dictionaries or
      two lists of equal length. Suppose `x` and `y` each contain
      :math:`d` variables:
  
      .. math:: D(x, y) = \\sum_i^d |x_i - y_i|
  
      Parameters
      ----------
      x : dict or list
          First input vector.
  
      y : dict or list
          Second input vector.
  
      Returns
      -------
      out : float
          Manhattan distance between `x` and `y`.
  
      Notes
      -----
      - If the input vectors are in dictionary form, keys missing in one
        of the two dictionaries are assumed to have value 0.
  
      - Manhattan distance is also known as "city block" or "taxi cab"
        distance.
  
      References
      ----------
      - `Wikipedia - taxicab geometry
        <http://en.wikipedia.org/wiki/Taxicab_geometry>`_
  
      Examples
      --------
      >>> tc.distances.manhattan([1, 2, 3], [4, 5, 6])
      9.0
      ...
      >>> tc.distances.manhattan({'a': 2, 'c': 4}, {'b': 3, 'c': 12})
      13.0
      """
      return _tc.extensions._distances.manhattan(x, y)
  
file_path: turicreate/src/python/turicreate/toolkits/distances/_distances.py
imports: from __future__ import print_function
  from __future__ import division
  from __future__ import absolute_import
  import turicreate
label_desc: Use image node_id 4 for calling a global function with example usage: manhattan(x, y) and returns: _tc