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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 full_name(self):
 """ The full name of the field. This is the field's entities name concatenated with the field's name. If the field is unnamed or not bound to an entity, the result respectively contains None. """


    entity = self.entity.__name__ if self.entity is not None else None
    name = self.name if self.name is not None else None
    if entity and name:
      return entity + '.' + name
    elif entity:
      return entity + '.<unnamed>'
    elif name:
      return '<unbound>.' + name
    else:
      return '<unbound>.<unnamed>'