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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 _from_rest_blank(model, props):
 """ Set empty strings to None where allowed This is done on fields with `allow_blank=True` which takes an incoming empty string & sets it to None so validations are skipped. This is useful on fields that aren't required with format validations like URLType, EmailType, etc. """


    blank = model.get_fields_by_prop('allow_blank', True)

    for field in blank:
        try:
            if props[field] == '':
                props[field] = None
        except KeyError:
            continue