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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 _fix_up(self, cls, code_name):
 """Internal helper called to tell the property its name. This is called by _fix_up_properties() which is called by MetaModel when finishing the construction of a Model subclass. The name passed in is the name of the class attribute to which the Property is assigned (a.k.a. the code name). Note that this means that each Property instance must be assigned to (at most) one class attribute. E.g. to declare three strings, you must call StringProperty() three times, you cannot write foo = bar = baz = StringProperty() """

    self._code_name = code_name
    if self._name is None:
      self._name = code_name