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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 frigg(branch: str):
 """ Performs necessary checks to ensure that the frigg build is one that should create releases. :param branch: The branch the environment should be running against. """

    assert os.environ.get('FRIGG_BUILD_BRANCH') == branch
    assert not os.environ.get('FRIGG_PULL_REQUEST')