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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 discover():
 """Find and load all available plugins. """

    plugin_files = []

    for plugin_dir in _get_plugin_dirs():
        if os.path.isdir(plugin_dir):
            for plugin_file in os.listdir(plugin_dir):
                if plugin_file.endswith(".py") and not plugin_file == "__init__.py":
                    plugin_files.append(os.path.join(plugin_dir, plugin_file))

    if rapport.config.get_int("rapport", "verbosity") >= 2:
        print("Found plugin modules: {0}".format(plugin_files))

    for plugin_file in plugin_files:
        if rapport.config.get_int("rapport", "verbosity") >= 2:
            print("Importing module {0}".format(_path_to_module(plugin_file)))
        __import__(_path_to_module(plugin_file))