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There are a few steps that can be taken to resolve this error:

1. Make sure that Jest is properly installed and configured in your project. Check that the Jest package is listed as a dev dependency in your package.json file and that you have a Jest configuration file (jest.config.js or package.json) in your project.

2. Check that you are calling the jest.replaceProperty() method correctly. The jest.replaceProperty() method is a member of the Jest library and should be called using the Jest object. For example, if you want to mock a constant value named MY_CONST, you would call jest.replaceProperty() like this:

const originalValue = MY_CONST;
jest.spyOn(global, 'MY_CONST', 'get').mockReturnValue('new value');

// ...

expect(MY_CONST).toEqual('new value');

// ...

global.MY_CONST = originalValue;

1. If you are still seeing the "jest.replaceProperty is not a function" error message, try checking your Jest version. The jest.replaceProperty() method was introduced in Jest 25.2.0, so make sure you are using a version of Jest that supports this feature.

2. If you are using an older version of Jest, you may need to use a different approach to mocking constants. One option is to use the Object.defineProperty() method to redefine the constant value at runtime:

const originalValue = MY_CONST;
Object.defineProperty(global, 'MY_CONST', { value: 'new value' });

// ...

expect(MY_CONST).toEqual('new value');

// ...

global.MY_CONST = originalValue;

This approach is a bit more verbose, but should work for older versions of Jest.