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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_all_plugins(self):
 """Load all the plugins in the plugin directory"""


        # Go through the existing python files in the plugin directory
        self.plugin_path = os.path.realpath(self.plugin_dir)
        sys.path.append(self.plugin_dir)
        print '<<< Plugin Manager >>>'
        for f in [os.path.join(self.plugin_dir, child) for child in os.listdir(self.plugin_dir)]:

            # Skip certain files
            if '.DS_Store' in f or '__init__.py' in f: 
                continue

            # Add the plugin
            self.add_plugin(f)