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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 add_local(self, source_fpath, version=None, tags=None):
 """Copies a given file into local store as an instance of this dataset. Parameters source_fpath : str The full path for the source file to use. version: str, optional The version of the instance of this dataset. tags : list of str, optional The tags associated with the given instance of this dataset. Returns ------- ext : str The extension of the file added. """

        ext = os.path.splitext(source_fpath)[1]
        ext = ext[1:]  # we dont need the dot
        fpath = self.fpath(version=version, tags=tags, ext=ext)
        shutil.copyfile(src=source_fpath, dst=fpath)
        return ext