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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 compute_output(self, o, output_shape=None):
 """Compute output of multihead attention. Args: o: a Tensor with dimensions query_heads_dims + {value_dim} + other_dims output_shape: an optional Shape Returns: a Tensor with shape: {output_dim} + other_dims """

    if self.combine_dims:
      o = mtf.transpose(o, o.shape - self.o_dims + self.o_dims)
      o = mtf.replace_dimensions(o, self.o_dims, self.wo.shape.dims[0])
      reduced_dims = [self.wo.shape.dims[0]]
    else:
      reduced_dims = self.o_dims
    return mtf.einsum(
        [o, self.wo], output_shape=output_shape, reduced_dims=reduced_dims)