<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def clean(self):
 """ Validation function that checks the dimensions of the crop whether it fits into the original and the format. """

        data = self.cleaned_data
        photo = data['photo']
        if (
            (data['crop_left'] > photo.width) or
            (data['crop_top'] > photo.height) or
            ((data['crop_left'] + data['crop_width']) > photo.width) or
            ((data['crop_top'] + data['crop_height']) > photo.height)
        ):
            # raise forms.ValidationError, ugettext("The specified crop coordinates do not fit into the source photo.")
            raise ValidationError(ugettext("The specified crop coordinates do not fit into the source photo."))
        return data