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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_secondary_sources( assignment_nodes, sources, lattice ):
 """ Sets the secondary_nodes attribute of each source in the sources list. Args: assignment_nodes([AssignmentNode]) sources([tuple]) lattice(Lattice):
 the lattice we're analysing. """

    for source in sources:
        source.secondary_nodes = find_assignments(assignment_nodes, source, lattice)