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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_rfc1918(ip):
 """Checks to see if an IP address is used for local communications within a private network as specified by RFC 1918 """

    if ip_between(ip, "10.0.0.0", "10.255.255.255"):
        return True
    elif ip_between(ip, "172.16.0.0", "172.31.255.255"):
        return True
    elif ip_between(ip, "192.168.0.0", "192.168.255.255"):
        return True
    else:
        return False