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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 build_vars(path=None):
 """Build initial vars."""

        init_vars = {
            "__name__": "__main__",
            "__package__": None,
            "reload": reload,
        }
        if path is not None:
            init_vars["__file__"] = fixpath(path)
        # put reserved_vars in for auto-completion purposes
        for var in reserved_vars:
            init_vars[var] = None
        return init_vars