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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 wrapper(ruby_string, wrapper_prefix, runas=None, *binaries):
    '''
    Install RVM wrapper scripts

    ruby_string
        Ruby/gemset to install wrappers for

    wrapper_prefix
        What to prepend to the name of the generated wrapper binaries

    runas
        The user under which to run rvm. If not specified, then rvm will be run
        as the user under which Salt is running.

    binaries : None
        The names of the binaries to create wrappers for. When nothing is
        given, wrappers for ruby, gem, rake, irb, rdoc, ri and testrb are
        generated.

    CLI Example:

    .. code-block:: bash

        salt '*' rvm.wrapper <ruby_string> <wrapper_prefix>
    '''
    cmd = ['wrapper', ruby_string, wrapper_prefix]
    cmd.extend(binaries)
    return _rvm(cmd, runas=runas)