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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 from_mapping(cls, mapping):
 """ Produces a set of parameters from a mapping """

        group = cls()
        for name, value in mapping.items():
            if name.startswith('_'):
                continue
            group[name] = Parameter(
                name=name,
                value=value,
                constraint=Parameter.constraint_from_type(value),
            )
        return group