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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 source_decode(sourcecode, verbose=0):
 """Decode operator source and import operator class. Parameters sourcecode: string a string of operator source (e.g 'sklearn.feature_selection.RFE') verbose: int, optional (default: 0) How much information TPOT communicates while it's running. 0 = none, 1 = minimal, 2 = high, 3 = all. if verbose > 2 then ImportError will rasie during initialization Returns ------- import_str: string a string of operator class source (e.g. 'sklearn.feature_selection') op_str: string a string of operator class (e.g. 'RFE') op_obj: object operator class (e.g. RFE) """

    tmp_path = sourcecode.split('.')
    op_str = tmp_path.pop()
    import_str = '.'.join(tmp_path)
    try:
        if sourcecode.startswith('tpot.'):
            exec('from {} import {}'.format(import_str[4:], op_str))
        else:
            exec('from {} import {}'.format(import_str, op_str))
        op_obj = eval(op_str)
    except Exception as e:
        if verbose > 2:
            raise ImportError('Error: could not import {}.\n{}'.format(sourcecode, e))
        else:
            print('Warning: {} is not available and will not be used by TPOT.'.format(sourcecode))
        op_obj = None

    return import_str, op_str, op_obj