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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 _generateFeatures(self):
 """ Generates a pool of features to be used for the experiments. For each index, numColumns SDR's are created, as locations for the same feature should be different for each column. """

    size = self.sensorInputSize
    bits = self.numInputBits

    self.features = []
    for _ in xrange(self.numColumns):
      self.features.append(
        [self._generatePattern(bits, size) for _ in xrange(self.numFeatures)]
    )