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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 make_prefix(api_version, manipulator, auth_type):
 """Make prefix string based on configuration parameters."""

    prefix = "%s_%s" % (api_version, manipulator)
    if (auth_type and auth_type != 'none'):
        prefix += '_' + auth_type
    return prefix