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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 extract_path(prec, v):
 """extracts a path in form of vertex list from source to vertex v given a precedence table prec leading to the source :param prec: precedence table of a tree :param v: vertex on the tree :returns: path from root to v, in form of a list :complexity: linear """

    L = []
    while v is not None:
        L.append(v)
        v = prec[v]
        assert v not in L   # prevent infinite loops for a bad formed table prec
    return L[::-1]