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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 sniff_field_spelling(mlog, source):
    '''attempt to detect whether APM or PX4 attributes names are in use'''
    position_field_type_default = position_field_types[0] # Default to PX4 spelling
    
    msg = mlog.recv_match(source)
    mlog._rewind() # Unfortunately it's either call this or return a mutated object
    
    position_field_selection = [spelling for spelling in position_field_types if hasattr(msg, spelling[0])]

    return position_field_selection[0] if position_field_selection else position_field_type_default