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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_pip_addons(_globals):
    '''Load all known fabsetup addons which are installed as pypi pip-packages.

    Args:
        _globals(dict): the globals() namespace of the fabric script.

    Return: None
    '''
    for package_name in known_pip_addons:
        _, username = package_username(package_name)
        try:
            load_addon(username, package_name.replace('-', '_'), _globals)
        except ImportError:
            pass