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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 prepend_path_variable_command(variable, paths):
 """ Returns a command that prepends the given paths to the named path variable on the current platform. """

    assert isinstance(variable, basestring)
    assert is_iterable_typed(paths, basestring)
    return path_variable_setting_command(
        variable, paths + [expand_variable(variable)])