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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 is_initialised( self ):
 """ Check whether the simulation has been initialised. Args: None Returns: None """

        if not self.lattice:
            raise AttributeError('Running a simulation needs the lattice to be initialised')
        if not self.atoms:
            raise AttributeError('Running a simulation needs the atoms to be initialised')
        if not self.number_of_jumps and not self.for_time:
            raise AttributeError('Running a simulation needs number_of_jumps or for_time to be set')