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venv/lib/python3.9/site-packages/sqlalchemy_utils/expressions.py

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+import sqlalchemy as sa
+from sqlalchemy.dialects import postgresql
+from sqlalchemy.ext.compiler import compiles
+from sqlalchemy.sql.expression import ColumnElement, FunctionElement
+from sqlalchemy.sql.functions import GenericFunction
+
+from .functions.orm import quote
+
+
+class array_get(FunctionElement):
+    name = 'array_get'
+
+
+@compiles(array_get)
+def compile_array_get(element, compiler, **kw):
+    args = list(element.clauses)
+    if len(args) != 2:
+        raise Exception(
+            "Function 'array_get' expects two arguments (%d given)." % len(args)
+        )
+
+    if not hasattr(args[1], 'value') or not isinstance(args[1].value, int):
+        raise Exception('Second argument should be an integer.')
+    return f'({compiler.process(args[0])})[{sa.text(str(args[1].value + 1))}]'
+
+
+class row_to_json(GenericFunction):
+    name = 'row_to_json'
+    type = postgresql.JSON
+
+
+@compiles(row_to_json, 'postgresql')
+def compile_row_to_json(element, compiler, **kw):
+    return f'{element.name}({compiler.process(element.clauses)})'
+
+
+class json_array_length(GenericFunction):
+    name = 'json_array_length'
+    type = sa.Integer
+
+
+@compiles(json_array_length, 'postgresql')
+def compile_json_array_length(element, compiler, **kw):
+    return f'{element.name}({compiler.process(element.clauses)})'
+
+
+class Asterisk(ColumnElement):
+    def __init__(self, selectable):
+        self.selectable = selectable
+
+
+@compiles(Asterisk)
+def compile_asterisk(element, compiler, **kw):
+    return '%s.*' % quote(compiler.dialect, element.selectable.name)