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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 validate_port_or_colon_separated_port_range(port_range):
 """Accepts a port number or a single-colon separated range."""

    if port_range.count(':') > 1:
        raise ValidationError(_("One colon allowed in port range"))
    ports = port_range.split(':')
    for port in ports:
        validate_port_range(port)