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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_patch_structure(self, data):
 """ Common validation of PATCH structure Provide check that 'value' present in all operations expect it. Provide check if 'path' is present. 'path' can be absent if provided without '/' at the start. Supposed that if 'path' is present than it is prepended with '/'. Removing '/' in the beginning to simplify usage in resource. """

        if data['op'] not in self.NO_VALUE_OPERATIONS and 'value' not in data:
            raise ValidationError('value is required')

        if 'path' not in data:
            raise ValidationError('Path is required and must always begin with /')
        else:
            data['field_name'] = data['path'][1:]