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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 is_type_I_branch(u, v, dfs_data):
 """Determines whether a branch uv is a type I branch."""

    if u != a(v, dfs_data):
        return False
    if u == L2(v, dfs_data):
        return True
    return False