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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 cast_number_strings_to_integers(d):
 """d is a dict"""

    for k, v in d.items():
        # print type(v)
        if determine_if_str_or_unicode(v):
            if v.isdigit():
                d[k] = int(v)
    return d