code: def modeldeclarations(self):
          
          lines = Lines()
          lines.add(0, '@cython.final')
          lines.add(0, 'cdef class Model(object):')
          lines.add(1, 'cdef public int idx_sim')
          lines.add(1, 'cdef public Parameters parameters')
          lines.add(1, 'cdef public Sequences sequences')
          if hasattr(self.model, 'numconsts'):
              lines.add(1, 'cdef public NumConsts numconsts')
          if hasattr(self.model, 'numvars'):
              lines.add(1, 'cdef public NumVars numvars')
          return lines
docs: Attribute declarations of the model class.