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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 _is_entity(bpe):
 """Return True if the element is a physical entity."""

    if isinstance(bpe, _bp('Protein')) or \
        isinstance(bpe, _bpimpl('Protein')) or \
        isinstance(bpe, _bp('SmallMolecule')) or \
        isinstance(bpe, _bpimpl('SmallMolecule')) or \
        isinstance(bpe, _bp('Complex')) or \
        isinstance(bpe, _bpimpl('Complex')) or \
        isinstance(bpe, _bp('Rna')) or \
        isinstance(bpe, _bpimpl('Rna')) or \
        isinstance(bpe, _bp('RnaRegion')) or \
        isinstance(bpe, _bpimpl('RnaRegion')) or \
        isinstance(bpe, _bp('DnaRegion')) or \
        isinstance(bpe, _bpimpl('DnaRegion')) or \
        isinstance(bpe, _bp('PhysicalEntity')) or \
        isinstance(bpe, _bpimpl('PhysicalEntity')):
        return True
    else:
        return False