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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 name(cls):
 """The URL name of this object, unique across all instances of this model"""

        if cls.__name_length__ is None:
            column_type = UnicodeText()
        else:
            column_type = Unicode(cls.__name_length__)
        if cls.__name_blank_allowed__:
            return Column(column_type, nullable=False, unique=True)
        else:
            return Column(column_type, CheckConstraint("name <> ''"), nullable=False, unique=True)