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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 find_primitive(cell, symprec=1e-5):
 """ A primitive cell is searched in the input cell. When a primitive cell is found, an object of Atoms class of the primitive cell is returned. When not, None is returned. """

    lattice, positions, numbers = spg.find_primitive(cell.totuple(), symprec)
    if lattice is None:
        return None
    else:
        return Atoms(numbers=numbers,
                     scaled_positions=positions,
                     cell=lattice,
                     pbc=True)