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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 count_base_units(units):
 """Returns a dict mapping names of base units to how many times they appear in the given iterable of units. Effectively this counts how many length units you have, how many time units, and so forth. """

    ret = {}
    for unit in units:
        factor, base_unit = get_conversion_factor(unit)

        ret.setdefault(base_unit, 0)
        ret[base_unit] += 1

    return ret