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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 _parse_requirements(self, input):
 """ Parse a list of requirements specifications. Lines that look like "foobar==1.0" are parsed; all other lines are silently ignored. Returns a tuple of tuples, where each inner tuple is: (package, version) """


        results = []

        for line in input:
            (package, version) = self._parse_line(line)
            if package:
                results.append((package, version))

        return tuple(results)