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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 _checkString(inputstring, description, minlength=0, maxlength=None):
 """Check that the given string is valid. Args: * inputstring (string):
 The string to be checked * description (string):
 Used in error messages for the checked inputstring * minlength (int):
 Minimum length of the string * maxlength (int or None):
 Maximum length of the string Raises: TypeError, ValueError Uses the function :func:`_checkInt` internally. """

    # Type checking
    if not isinstance(description, str):
        raise TypeError('The description should be a string. Given: {0!r}'.format(description))

    if not isinstance(inputstring, str):
        raise TypeError('The {0} should be a string. Given: {1!r}'.format(description, inputstring))

    if not isinstance(maxlength, (int, type(None))):
        raise TypeError('The maxlength must be an integer or None. Given: {0!r}'.format(maxlength))

    # Check values
    _checkInt(minlength, minvalue=0, maxvalue=None, description='minlength')

    if len(inputstring) < minlength:
        raise ValueError('The {0} is too short: {1}, but minimum value is {2}. Given: {3!r}'.format( \
            description, len(inputstring), minlength, inputstring))

    if not maxlength is None:
        if maxlength < 0:
            raise ValueError('The maxlength must be positive. Given: {0}'.format(maxlength))

        if maxlength < minlength:
            raise ValueError('The maxlength must not be smaller than minlength. Given: {0} and {1}'.format( \
                maxlength, minlength))

        if len(inputstring) > maxlength:
            raise ValueError('The {0} is too long: {1}, but maximum value is {2}. Given: {3!r}'.format( \
                description, len(inputstring), maxlength, inputstring))