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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 load_libzbar():
 """Loads the zbar shared library and its dependencies. Populates the globals LIBZBAR and EXTERNAL_DEPENDENCIES. """

    global LIBZBAR
    global EXTERNAL_DEPENDENCIES
    if not LIBZBAR:
        libzbar, dependencies = zbar_library.load()
        LIBZBAR = libzbar
        EXTERNAL_DEPENDENCIES = [LIBZBAR] + dependencies

    return LIBZBAR