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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 remove_species(self, species):
 """ Remove all occurrences of a species from a molecule. Args: species: Species to remove. """

        new_sites = []
        species = [get_el_sp(sp) for sp in species]
        for site in self._sites:
            new_sp_occu = {sp: amt for sp, amt in site.species.items()
                           if sp not in species}
            if len(new_sp_occu) > 0:
                new_sites.append(Site(new_sp_occu, site.coords,
                                      properties=site.properties))
        self._sites = new_sites