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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 check_string(value, min_length=None, max_length=None, pattern=None):
 """ verify that a string has a particular size and conforms to a particular alphabet False False False False False False True True True True True False False True False """

    if type(value) not in [str, unicode]:
        return False

    if min_length and len(value) < min_length:
        return False

    if max_length and len(value) > max_length:
        return False

    if pattern and not re.match(pattern, value):
        return False

    return True