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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 detect_converters(pattern: str, converter_dict: Dict[str, Callable], default: Callable = str):
 """ detect pairs of varname and converter from pattern"""

    converters = {}
    for matched in VARS_PT.finditer(pattern):
        matchdict = matched.groupdict()
        varname = matchdict['varname']
        converter = matchdict['converter']
        converters[varname] = converter_dict.get(converter, default)
    return converters