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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 get_field_label_css_class(self, bound_field):
 """ Returns 'form-check-label' if widget is CheckboxInput. For all other fields, no css class is added. """

        # If we render CheckboxInputs, Bootstrap requires a different
        # field label css class for checkboxes.
        if isinstance(bound_field.field.widget, forms.CheckboxInput):
            return 'form-check-label'

        return super().get_field_label_css_class(bound_field)