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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 value_for_element(cls, elem):
 """Deserialize the given XML `Element` into its representative value. Depending on the content of the element, the returned value may be: * a string, integer, or boolean value * a `datetime.datetime` instance * a list of `Resource` instances * a single `Resource` instance * a `Money` instance * ``None`` """

        log = logging.getLogger('recurly.resource')
        if elem is None:
            log.debug("Converting %r element into None value", elem)
            return

        if elem.attrib.get('nil') is not None:
            log.debug("Converting %r element with nil attribute into None value", elem.tag)
            return

        if elem.tag.endswith('_in_cents') and 'currency' not in cls.attributes and not cls.inherits_currency:
            log.debug("Converting %r element in class with no matching 'currency' into a Money value", elem.tag)
            return Money.from_element(elem)

        attr_type = elem.attrib.get('type')
        log.debug("Converting %r element with type %r", elem.tag, attr_type)

        if attr_type == 'integer':
            return int(elem.text.strip())
        if attr_type == 'float':
            return float(elem.text.strip())
        if attr_type == 'boolean':
            return elem.text.strip() == 'true'
        if attr_type == 'datetime':
            return iso8601.parse_date(elem.text.strip())
        if attr_type == 'array':
            return [cls._subclass_for_nodename(sub_elem.tag).from_element(sub_elem) for sub_elem in elem]

        # Unknown types may be the names of resource classes.
        if attr_type is not None:
            try:
                value_class = cls._subclass_for_nodename(attr_type)
            except ValueError:
                log.debug("Not converting %r element with type %r to a resource as that matches no known nodename",
                    elem.tag, attr_type)
            else:
                return value_class.from_element(elem)

        # Untyped complex elements should still be resource instances. Guess from the nodename.
        if len(elem):  # has children
            value_class = cls._subclass_for_nodename(elem.tag)
            log.debug("Converting %r tag into a %s", elem.tag, value_class.__name__)
            return value_class.from_element(elem)

        value = elem.text or ''
        return value.strip()