code: def from_filenames(filenames, transformations=None, primitive=True,
                         extend_collection=False):
          
  
          allcifs = []
          for fname in filenames:
              with open(fname, "r") as f:
                  allcifs.append(f.read())
          return CifTransmuter("\n".join(allcifs), transformations,
                               primitive=primitive,
                               extend_collection=extend_collection)
docs: Generates a TransformedStructureCollection from a cif, possibly
          containing multiple structures.
  
          Args:
              filenames: List of strings of the cif files
              transformations: New transformations to be applied to all
                  structures
              primitive: Same meaning as in __init__.
              extend_collection: Same meaning as in __init__.