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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 parse_compound(compound_def, context=None):
 """Parse a structured compound definition as obtained from a YAML file Returns a CompoundEntry."""


    compound_id = compound_def.get('id')
    _check_id(compound_id, 'Compound')

    mark = FileMark(context, None, None)
    return CompoundEntry(compound_def, mark)