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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 runtime_to_build(runtime_deps):
 """Adds all runtime deps to build deps"""

    build_deps = copy.deepcopy(runtime_deps)
    for dep in build_deps:
        if len(dep) > 0:
            dep[0] = 'BuildRequires'
    return build_deps