def add_includes(*, libs: list[str]) -> str:
    """
    Builds a str of includes,

    >>> add_includes(libs=[cstring, string, stdio])
    '''#include <cstring>
    #include <string>
    #include stdio
    '''
    """
    lib = ["#include " + (f"<{lib}>" if "/" not in lib else f'"{lib}"') for lib in libs]
    return "\n".join(lib) + "\n"