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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 get_linenumbers(functions, module, searchstr='def {}(image):
\n'):
 """Returns a dictionary which maps function names to line numbers. Args: functions: a list of function names module: the module to look the functions up searchstr: the string to search for Returns: A dictionary with functions as keys and their line numbers as values. """

    lines = inspect.getsourcelines(module)[0]
    line_numbers = {}
    for function in functions:
        try:
            line_numbers[function] = lines.index(
                    searchstr.format(function)) + 1
        except ValueError:
            print(r'Can not find `{}`'.format(searchstr.format(function)))
            line_numbers[function] = 0
    return line_numbers