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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_feature_api(project, force=False):
 """Validate feature API"""

    if not force and not project.on_pr():
        raise SkippedValidationTest('Not on PR')

    validator = FeatureApiValidator(project)
    result = validator.validate()
    if not result:
        raise InvalidFeatureApi