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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 validate(self, require_all=True, scale='colors'):
 """Validate the visualization contents. Parameters require_all : boolean, default True If True (default), then all fields ``data``, ``scales``, ``axes``, and ``marks`` must be defined. The user is allowed to disable this if the intent is to define the elements client-side. If the contents of the visualization are not valid Vega, then a :class:`ValidationError` is raised. """

        super(self.__class__, self).validate()
        required_attribs = ('data', 'scales', 'axes', 'marks')
        for elem in required_attribs:
            attr = getattr(self, elem)
            if attr:
                # Validate each element of the sets of data, etc
                for entry in attr:
                    entry.validate()
                names = [a.name for a in attr]
                if len(names) != len(set(names)):
                    raise ValidationError(elem + ' has duplicate names')
            elif require_all:
                raise ValidationError(
                    elem + ' must be defined for valid visualization')