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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 check_vector_template(self):
 """Determines if features are defined as vector source based on MapViz arguments."""


        if self.vector_url is not None and self.vector_layer_name is not None:
            self.template = 'vector_' + self.template
            self.vector_source = True
        else:
            self.vector_source = False