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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 _set_field_if_present(cls, block, name, value, attrs):
 """Sets the field block.name, if block have such a field."""

        if name in block.fields:
            value = (block.fields[name]).from_string(value)
            if "none" in attrs and attrs["none"] == "true":
                setattr(block, name, None)
            else:
                setattr(block, name, value)
        else:
            logging.warning("XBlock %s does not contain field %s", type(block), name)