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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(cls, f):
 """Read WETRecord from file. Records end with 2 blank lines."""

    header = WETHeader.read(f)
    if header is None:
      # EOF
      return None
    content = f.read(header.length)

    # Consume empty separators
    f.readline()
    f.readline()

    return cls(header.url, content)