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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 spec(self, name):
 """ Returns either the input corresponding to a fileset or field field spec or a spec or parameter that has either been passed to the study as an input or can be derived. Parameters name : Str | BaseData | Parameter A parameter, fileset or field or name of one """

        # If the provided "name" is actually a data item or parameter then
        # replace it with its name.
        if isinstance(name, (BaseData, Parameter)):
            name = name.name
        # If name is a parameter than return the parameter spec
        if name in self._param_specs:
            return self._param_specs[name]
        else:
            return self.bound_spec(name)