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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_schema_field(schema, field):
 """Get the schema field of a model field :param Schema schema: a marshmallow schema :param str field: the name of the model field :return str: the name of the field in the schema """

    schema_fields_to_model = {key: get_model_field(schema, key) for (key, value) in schema._declared_fields.items()}
    for key, value in schema_fields_to_model.items():
        if value == field:
            return key

    raise Exception("Couldn't find schema field from {}".format(field))