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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 annualization_factor(period, annualization):
 """ Return annualization factor from period entered or if a custom value is passed in. Parameters period : str, optional Defines the periodicity of the 'returns' data for purposes of annualizing. Value ignored if `annualization` parameter is specified. Defaults are:: 'monthly':12 'weekly': 52 'daily': 252 annualization : int, optional Used to suppress default values available in `period` to convert returns into annual returns. Value should be the annual frequency of `returns`. Returns ------- annualization_factor : float """

    if annualization is None:
        try:
            factor = ANNUALIZATION_FACTORS[period]
        except KeyError:
            raise ValueError(
                "Period cannot be '{}'. "
                "Can be '{}'.".format(
                    period, "', '".join(ANNUALIZATION_FACTORS.keys())
                )
            )
    else:
        factor = annualization
    return factor