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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 get_ip_prefixes_from_bird(filename):
 """Build a list of IP prefixes found in Bird configuration. Arguments: filename (str):
 The absolute path of the Bird configuration file. Notes: It can only parse a file with the following format define ACAST_PS_ADVERTISE = [ 10.189.200.155/32, 10.189.200.255/32 ]; Returns: A list of IP prefixes. """

    prefixes = []
    with open(filename, 'r') as bird_conf:
        lines = bird_conf.read()

    for line in lines.splitlines():
        line = line.strip(', ')
        if valid_ip_prefix(line):
            prefixes.append(line)

    return prefixes