Adding cython v0.20.2 in third-party.

third_party/cython/src/Cython/Includes/cpython/sequence.pxd

Index: third_party/cython/src/Cython/Includes/cpython/sequence.pxd
diff --git a/third_party/cython/src/Cython/Includes/cpython/sequence.pxd b/third_party/cython/src/Cython/Includes/cpython/sequence.pxd
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+from cpython.ref cimport PyObject
+
+cdef extern from "Python.h":
+
+    ############################################################################
+    # 6.3 Sequence Protocol
+    ############################################################################
+
+    bint PySequence_Check(object o)
+    # Return 1 if the object provides sequence protocol, and 0
+    # otherwise. This function always succeeds.
+
+    Py_ssize_t PySequence_Size(object o) except -1
+    # Returns the number of objects in sequence o on success, and -1
+    # on failure. For objects that do not provide sequence protocol,
+    # this is equivalent to the Python expression "len(o)".
+
+    Py_ssize_t PySequence_Length(object o) except -1
+    # Alternate name for PySequence_Size().
+
+    object PySequence_Concat(object o1, object o2)
+    # Return value: New reference.
+    # Return the concatenation of o1 and o2 on success, and NULL on
+    # failure. This is the equivalent of the Python expression "o1 +
+    # o2".
+
+    object PySequence_Repeat(object o, Py_ssize_t count)
+    # Return value: New reference.
+    # Return the result of repeating sequence object o count times, or
+    # NULL on failure. This is the equivalent of the Python expression
+    # "o * count".
+
+    object PySequence_InPlaceConcat(object o1, object o2)
+    # Return value: New reference.
+    # Return the concatenation of o1 and o2 on success, and NULL on
+    # failure. The operation is done in-place when o1 supports
+    # it. This is the equivalent of the Python expression "o1 += o2".
+
+    object PySequence_InPlaceRepeat(object o, Py_ssize_t count)
+    # Return value: New reference.
+    # Return the result of repeating sequence object o count times, or
+    # NULL on failure. The operation is done in-place when o supports
+    # it. This is the equivalent of the Python expression "o *=
+    # count".
+
+    object PySequence_GetItem(object o, Py_ssize_t i)
+    # Return value: New reference.
+    # Return the ith element of o, or NULL on failure. This is the
+    # equivalent of the Python expression "o[i]".
+
+    object PySequence_GetSlice(object o, Py_ssize_t i1, Py_ssize_t i2)
+    # Return value: New reference.
+    # Return the slice of sequence object o between i1 and i2, or NULL
+    # on failure. This is the equivalent of the Python expression
+    # "o[i1:i2]".
+
+    int PySequence_SetItem(object o, Py_ssize_t i, object v) except -1
+    # Assign object v to the ith element of o. Returns -1 on
+    # failure. This is the equivalent of the Python statement "o[i] =
+    # v". This function does not steal a reference to v.
+
+    int PySequence_DelItem(object o, Py_ssize_t i) except -1
+    # Delete the ith element of object o. Returns -1 on failure. This
+    # is the equivalent of the Python statement "del o[i]".
+
+    int PySequence_SetSlice(object o, Py_ssize_t i1, Py_ssize_t i2, object v) except -1
+    # Assign the sequence object v to the slice in sequence object o
+    # from i1 to i2. This is the equivalent of the Python statement
+    # "o[i1:i2] = v".
+
+    int PySequence_DelSlice(object o, Py_ssize_t i1, Py_ssize_t i2) except -1
+    # Delete the slice in sequence object o from i1 to i2. Returns -1
+    # on failure. This is the equivalent of the Python statement "del
+    # o[i1:i2]".
+
+    int PySequence_Count(object o, object value) except -1
+    # Return the number of occurrences of value in o, that is, return
+    # the number of keys for which o[key] == value. On failure, return
+    # -1. This is equivalent to the Python expression
+    # "o.count(value)".
+
+    int PySequence_Contains(object o, object value) except -1
+    # Determine if o contains value. If an item in o is equal to
+    # value, return 1, otherwise return 0. On error, return -1. This
+    # is equivalent to the Python expression "value in o".
+
+    Py_ssize_t PySequence_Index(object o, object value) except -1
+    # Return the first index i for which o[i] == value. On error,
+    # return -1. This is equivalent to the Python expression
+    # "o.index(value)".
+
+    object PySequence_List(object o)
+    # Return value: New reference.
+    # Return a list object with the same contents as the arbitrary
+    # sequence o. The returned list is guaranteed to be new.
+
+    object PySequence_Tuple(object o)
+    # Return value: New reference.
+    # Return a tuple object with the same contents as the arbitrary
+    # sequence o or NULL on failure. If o is a tuple, a new reference
+    # will be returned, otherwise a tuple will be constructed with the
+    # appropriate contents. This is equivalent to the Python
+    # expression "tuple(o)".
+
+    object PySequence_Fast(object o, char *m)
+    # Return value: New reference.
+    # Returns the sequence o as a tuple, unless it is already a tuple
+    # or list, in which case o is returned. Use
+    # PySequence_Fast_GET_ITEM() to access the members of the
+    # result. Returns NULL on failure. If the object is not a
+    # sequence, raises TypeError with m as the message text.
+
+    PyObject* PySequence_Fast_GET_ITEM(object o, Py_ssize_t i)
+    # Return value: Borrowed reference.
+    # Return the ith element of o, assuming that o was returned by
+    # PySequence_Fast(), o is not NULL, and that i is within bounds.
+
+    PyObject** PySequence_Fast_ITEMS(object o)
+    # Return the underlying array of PyObject pointers. Assumes that o
+    # was returned by PySequence_Fast() and o is not NULL.
+
+    object PySequence_ITEM(object o, Py_ssize_t i)
+    # Return value: New reference.
+    # Return the ith element of o or NULL on failure. Macro form of
+    # PySequence_GetItem() but without checking that
+    # PySequence_Check(o) is true and without adjustment for negative
+    # indices.
+
+    Py_ssize_t PySequence_Fast_GET_SIZE(object o)
+    # Returns the length of o, assuming that o was returned by
+    # PySequence_Fast() and that o is not NULL. The size can also be
+    # gotten by calling PySequence_Size() on o, but
+    # PySequence_Fast_GET_SIZE() is faster because it can assume o is
+    # a list or tuple.
+
+