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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 schema_delete_field(cls, key):
 """Deletes a field."""

        root = '/'.join([API_ROOT, 'schemas', cls.__name__])
        payload = {
            'className': cls.__name__,
            'fields': {
                key: {
                    '__op': 'Delete'
                }
            }
        }
        cls.PUT(root, **payload)