class_docstr: The :class:`Layer` class represents a single layer of a neural network. It
  should be subclassed when implementing new types of layers.
  
  Because each layer can keep track of the layer(s) feeding into it, a
  network's output :class:`Layer` instance can double as a handle to the full
  network.
  
  Parameters
  ----------
  incoming : a :class:`Layer` instance or a tuple
      The layer feeding into this layer, or the expected input shape.
  name : a string or None
      An optional name to attach to this layer.
class_docstr_tok: ["The",":","class",":","`","Layer","`","class","represents","a","single","layer","of","a","neural","network",".","It","should","be","subclassed","when","implementing","new","types","of","layers",".","Because","each","layer","can","keep","track","of","the","layer","(","s",")","feeding","into","it",",","a","network","'s","output",":","class",":","`","Layer","`","instance","can","double","as","a","handle","to","the","full","network",".","Parameters","--","--","--","--","--","incoming",":","a",":","class",":","`","Layer","`","instance","or","a","tuple","The","layer","feeding","into","this","layer",",","or","the","expected","input","shape",".","name",":","a","string","or","None","An","optional","name","to","attach","to","this","layer","."]
code: def output_shape(self):
      shape = self.get_output_shape_for(self.input_shape)
      if any(isinstance(s, T.Variable) for s in shape):
          raise ValueError(
              "%s returned a symbolic output shape from its "
              "get_output_shape_for() method: %r. This is not "
              "allowed; shapes must be tuples of integers for "
              "fixed-size dimensions and Nones for variable "
              "dimensions." % (self.__class__.__name__, shape)
          )
      return shape
  
file_path: Lasagne/lasagne/layers/base.py
imports: from collections import OrderedDict
  import theano.tensor
  from ..None import utils
label_desc: Use image node_id 2 for calling the Layer obj's underlying member method code with example usage: obj.output_shape() and returns: shape