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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_plugins(namespace, instantiate=True):
 """ Loads all the plugins for the given namespace Args: namespace(str):
 Namespace string, as in the setuptools entry_points instantiate(bool):
 If true, will instantiate the plugins too Returns: dict of str, object: Returns the list of loaded plugins """

    mgr = ExtensionManager(
        namespace=namespace,
        on_load_failure_callback=(
            lambda _, ep, err: LOGGER.
            warning('Could not load plugin {}: {}'.format(ep.name, err))
        )
    )
    if instantiate:
        plugins = dict(
            (
                ext.name,
                ext.plugin if isinstance(ext.plugin, Plugin) else ext.plugin()
            ) for ext in mgr
        )
    else:
        plugins = dict((ext.name, ext.plugin) for ext in mgr)

    return plugins