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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 get_parents(docgraph, child_node, strict=True):
 """Return a list of parent nodes that dominate this child. In a 'syntax tree' a node never has more than one parent node dominating it. To enforce this, set strict=True. Parameters docgraph : DiscourseDocumentGraph a document graph strict : bool If True, raise a ValueError if a child node is dominated by more than one parent node. Returns ------- parents : list a list of (parent) node IDs. """

    parents = []
    for src, _, edge_attrs in docgraph.in_edges(child_node, data=True):
        if edge_attrs['edge_type'] == EdgeTypes.dominance_relation:
            parents.append(src)

    if strict and len(parents) > 1:
        raise ValueError(("In a syntax tree, a node can't be "
                          "dominated by more than one parent"))
    return parents