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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 get_all_instance_profiles(path_prefix='/', region=None, key=None,
                              keyid=None, profile=None):
    '''
    Get and return all IAM instance profiles, starting at the optional path.

    .. versionadded:: 2016.11.0

    CLI Example:

        salt-call boto_iam.get_all_instance_profiles
    '''
    conn = _get_conn(region=region, key=key, keyid=keyid, profile=profile)
    marker = False
    profiles = []
    while marker is not None:
        marker = marker if marker else None
        p = conn.list_instance_profiles(path_prefix=path_prefix,
                                                   marker=marker)
        res = p.list_instance_profiles_response.list_instance_profiles_result
        profiles += res.instance_profiles
        marker = getattr(res, 'marker', None)
    return profiles