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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 unload_plugin(name, category=None):
 """ remove single plugin Parameters name : str plugin name category : str plugin category Examples -------- {'decoders': {}, 'encoders': {}, 'parsers': {}} {'decoders': {'example': 'a decoder for dicts containing _example_ key'}, 'encoders': {}, 'parsers': {}} {'decoders': {}, 'encoders': {}, 'parsers': {}} """

    if category is not None:
        _all_plugins[category].pop(name)
    else:
        for cat in _all_plugins:
            if name in _all_plugins[cat]:
                _all_plugins[cat].pop(name)