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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 GetAPIScope(api_name):
 """Retrieves the scope for the given API name. Args: api_name: A string identifying the name of the API we want to retrieve a scope for. Returns: A string that is the scope for the given API name. Raises: GoogleAdsValueError: If the given api_name is invalid; accepted values are "adwords" and "ad_manager". """

  try:
    return SCOPES[api_name]
  except KeyError:
    raise googleads.errors.GoogleAdsValueError(
        'Invalid API name "%s" provided. Acceptable values are: %s' %
        (api_name, SCOPES.keys()))