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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 dumps(obj, pretty=False, escaped=True):
 """ Serialize ``obj`` to a VDF formatted ``str``. """

    if not isinstance(obj, dict):
        raise TypeError("Expected data to be an instance of``dict``")
    if not isinstance(pretty, bool):
        raise TypeError("Expected pretty to be of type bool")
    if not isinstance(escaped, bool):
        raise TypeError("Expected escaped to be of type bool")

    return ''.join(_dump_gen(obj, pretty, escaped))