def __init__(self, spec_path, product_name, feature_list):
self.product_specs = self._read(spec_path, product_name)<EOL>self.feature_list = feature_list<EOL>self.errors_mandatory = []<EOL>self.errors_never = []<EOL>
Constructor
:param spec_path: file path to the product spec json
:param product_name: the name of the product to extract the concrete spec
:param feature_list: the list of features that will be checked