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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 class_to_str(obj):
 """ get class string from object Examples -------- 'list' """

    mod_str = obj.__module__
    name_str = obj.__name__
    if mod_str == '__main__':
        return name_str
    else:
        return '.'.join([mod_str, name_str])