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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 str_to_bitstring(data):
 """Convert a string to a list of bits"""

    assert isinstance(data, bytes), "Data must be an instance of bytes"
    byte_list = data_to_byte_list(data)
    bit_list = [bit for data_byte in byte_list for bit in byte_to_bitstring(data_byte)]
    return bit_list