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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 is_plugin_installed(name):
 """Check if a plugin is installed, even if it's not enabled. :param name: Name of the plugin to check. :type name: string :return: If the plugin is installed. :rtype: bool """

    for directory in plugin_paths:
        if isdir(join(directory, name)):
            return True
    return False