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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def shift_by_n_processors(self, x, mesh_axis, offset, wrap):
 """Receive the slice from processor pcoord - offset. Args: x: a LaidOutTensor mesh_axis: an integer offset: an integer wrap: a boolean. If True, then wrap around. Otherwise, pad with zeros. """

    n = self.shape[mesh_axis].size
    source_pcoord = []
    for i in xrange(n):
      c = i - offset
      if c != c % n:
        if wrap:
          c = c % n
        else:
          c = None
      source_pcoord.append(c)
    return self.receive(x, mesh_axis, source_pcoord)