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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 to_int(d, key, default_to_zero=False, default=None, required=True):
 """Pull a value from the dict and convert to int :param default_to_zero: If the value is None or empty, treat it as zero :param default: If the value is missing in the dict use this default """

    value = d.get(key) or default
    if (value in ["", None]) and default_to_zero:
        return 0
    if value is None:
        if required:
            raise ParseError("Unable to read %s from %s" % (key, d))
    else:
        return int(value)