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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 _read_bytes(fp, buf):
 """Read bytes from a file-like object @param fp: File-like object that implements read(int) @type fp: file @param buf: Buffer to read into @type buf: bytes @return: buf """


    # Do the first read without resizing the input buffer
    offset = 0
    remaining = len(buf)
    while remaining > 0:
        l = fp.readinto((ctypes.c_char * remaining).from_buffer(buf, offset))
        if l is None or l == 0:
            return offset
        offset += l
        remaining -= l
    return offset