parameters: (self, timestep)
return_statement: return timestep in self.timesteps
docstring: Return 'True' if the given timestep exists.
  
          Examples:
          >>> model.timestep_exists(0.0)
docstring_summary: Return 'True' if the given timestep exists.
docstring_tokens: Return True if the given timestep exists .
function: def timestep_exists(self, timestep):
          """
          Return 'True' if the given timestep exists.
  
          Examples:
          >>> model.timestep_exists(0.0)
  
          """
          return timestep in self.timesteps
function_tokens: def timestep_exists ( self , timestep ) : return timestep in self . timesteps