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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 compute_checksum(filename, max_length=2**20):
 """Compute the CRC32 checksum for specified file Optional parameter max_length sets the maximum number of bytes used to limit time used with large files. Default = 2**20 (1MB) """


    fid = open(filename, 'rb') # Use binary for portability
    crcval = safe_crc(fid.read(max_length))
    fid.close()

    return crcval