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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 is_ip(string):
 """ Returns True if the given string is an IPv4 address, False otherwise. :type string: string :param string: Any string. :rtype: bool :return: True if the string is an IP address, False otherwise. """

    mo = re.match(r'(\d+)\.(\d+)\.(\d+)\.(\d+)', string)
    if mo is None:
        return False
    for group in mo.groups():
        if int(group) not in list(range(0, 256)):
            return False
    return True