code: def from_structures(cls, structures, constant_lattice=True, **kwargs):
          
          frac_coords = [structure.frac_coords for structure in structures]
          if constant_lattice:
              lattice = structures[0].lattice.matrix
          else:
              lattice = [structure.lattice.matrix for structure in structures]
          site_properties = [structure.site_properties for structure in structures]
          return cls(lattice, structures[0].species, frac_coords, site_properties=site_properties,
                     constant_lattice=constant_lattice, **kwargs)
docs: Convenience constructor to obtain trajectory from a list of structures.
          Note: Assumes no atoms removed during simulation
  
          Args:
              structures (list): list of pymatgen Structure objects.
              constant_lattice (bool): Whether the lattice changes during the simulation, such as in an NPT MD
                  simulation. True results in
  
          Returns:
              (Trajectory)