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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 copy_and_sum_families(family_source, family_target):
 """ methods iterates thru source family and copies its entries to target family in case key already exists in both families - then the values are added"""

    for every in family_source:
        if every not in family_target:
            family_target[every] = family_source[every]
        else:
            family_target[every] += family_source[every]