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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 load(klass, filename, inject_env=True):
 """Load a Pipfile from a given filename."""

        p = PipfileParser(filename=filename)
        pipfile = klass(filename=filename)
        pipfile.data = p.parse(inject_env=inject_env)
        return pipfile