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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 check_sha1(filename, sha1_hash):
 """Check whether the sha1 hash of the file content matches the expected hash. Parameters filename : str Path to the file. sha1_hash : str Expected sha1 hash in hexadecimal digits. Returns ------- bool Whether the file content matches the expected hash. """

    sha1 = hashlib.sha1()
    with open(filename, 'rb') as f:
        while True:
            data = f.read(1048576)
            if not data:
                break
            sha1.update(data)

    return sha1.hexdigest() == sha1_hash